NASA 1993 SBIR Phase 2 Solicitation
Project Title:
Fluid-Structure Interaction Using Unstructured Meshes
Fluent Inc.
10 Cavendish Court, Centerra Resource Park
Lebanon, NH 03766
93-101.01 2600 C AMOUNT REQUESTED $ 69,770
Fluid-Structure Interaction Using Unstructured Meshes
Abstract:
The objective of the proposed work is to develop a unified and
optimum numerical method for solving fluid-structure interaction
problems. We propose to use an unstructured solution-adaptive
topology for both fluid and structure, and to discretize the
governing equations for both using a common numerical basis. We
also propose to use MIMD parallel processing with domain
decomposition to allow the solution of these large three-
dimensional unsteady problems.
Phase I of the proposed work will concentrate on the fluid side,
and develop a numerical basis for computing fluid flow on a moving
and deforming mesh. Algorithms for the transmittal of a prescribed
boundary deformation to the interior unstructured mesh will be
developed. The methodology will be validated against the
literature. Phase II will concentrate on the discretization of the
structure equations, and the computation fluid-structure
interaction. Procedures for parallel processing of the code on MIMD
architectures will be also implemented. The resulting software will
address a wide variety of practical fluid-structure interaction
problems.
The software developed here will find application in a wide variety
of industrial problems. Examples include the computation of
aeroelasticity, the computation of blade flutter in turbomachinery,
valve flutter in internal flows, and the calculation of flow-
induced vibrations in heat-exchangers, and around high-rise
structures
Fluid, Structure, Unstructured-Mesh, Computational, Fluid,
Dynamics, Galerkin, Control-Volume
Project Title:
EFFICIENT COOLING OF TURBINE DISKS
Creare Incorporated
P.O. Box 71
Hanover, NH 03755
93-101.01 3800 AMOUNT REQUESTED $69,958
EFFICIENT COOLING OF TURBINE DISKS
Abstract:
In this program Creare will develop test data and design methods
for confident design of efficient cooling systems for turbine disks
in aircraft gas turbine engines. Cooling systems must prevent
ingress of hot combustion gases into the cavity between the turbine
disk and its stator when there is an intense, swirling flow past
the turbine disk from the turbine nozzles. In previous tests at
Creare, this swirling flow has been found to increase the cooling
flow requirements. We propose to develop a body of test data
applying to basic disk/stator configurations, simple theory to
assess the effects of design changes, and qualified computational
models for detailed assessment of designs. Innovations are: (1) a
small, low-speed test facility in which water is used to simulate,
observe, and measure the flow in the disk/stator gap of a gas
turbine, and (2) original mechanistic design models based on
analysis of the forces which govern the flow in the gap. In Phase
I we will prove the feasibility of our approach by developing a
basic theory for the effects of external flow on the required
cooling flow and showing that theoretical predictions agree with
Creare's existing database of test results. In Phase II we will
perform detailed tests using flow models which simulate aircraft
engines and develop qualified theory and computational models for
cooling system design.
Results of this program are important for manufacturers of aircraft
gas turbines, who require design methods for efficient disk cooling
systems. Results are also important for manufacturers of energy
recovery turbines used in the chemical process and petrochemical
industries. These turbines may operate with highly corrosive
process gases and sealing the turbine disk from the process gas is
vital.
gas turbines, disk cooling
Project Title:
Unstructured Density-Based CFD Methodology for Gas Turbine Combustors
CFD Research Corp.
3325 Triana Blvd.
Huntsville, AL 35805
93-101.01 6576 __ AMOUNT REQUESTED $70,000
Unstructured Density-Based CFD Methodology for Gas Turbine Combustors
Abstract:
Innovative unstructured, density-based CFD methodology will be
developed in this project applicable to low-speed, turbulent
reacting flows. In Phase I, the feasibility of using finite rate
kinetics in an unstructured CFD environment will be addressed. An
existing unstructured, density-based, implicit CFD code, CFD
FASTRAN, will be used as a starting point. First, the code will be
modified for low-speed flows by incorporating existing pre-
conditioning matrix methods. Second, at least two multi-step
finite-rate hydrocarbon-air combustion models will be implemented
and tested. Comparison of computational efficiency will be made to
current structured, pressure-based CFD methodology. And last, for
full 3-D demonstration, an annular gas turbine combustor will be
modeled and analyzed. In Phase II, spray models, conjugate heat
transfer, and other advanced physical models required for combustor
analysis will be incorporated and validated. The developed
unstructured methodology will also be implemented into the NASA
LeRC ALLSPD code.
The CFD methodology will be packaged into a commercial software
code (as part of Phase III) and licensed to gas turbine engine
manufacturers such as Solar, Westinghouse, Allison, Allied Signal,
General Electric, P&W, etc. The code will have direct application
to combustor design, especially to the NASA High Speed Civil
Transport and Advanced Subsonics Engines. In addition, due to its
ability to model low and high speed flows with finite-rate
chemistry, the code will also be applicable to other engine
components, e.g., inlets, nozzles, etc.
unstructured, finite-rate chemistry, Navier-Stokes, implicit fully
coupled, gas turbine combustors
Project Title:
Turbomachinery Vibration - Analysis With a New Parallel Time Decomposition Scheme
Continuum Dynamic, Inc.
P.O. Box 3073
Princeton, NJ 08543-3073
93-101.01 9282 __ AMOUNT REQUESTED $ 69,169.37
Turbomachinery Vibration - Analysis With a New Parallel Time Decomposition Scheme
Abstract:
Current time-marching methods for assessing periodic blade loads
consume inordinate computational time, greatly restricting analysis
and design based on such approaches. This study seeks to redress
this drawback by implementing a novel time-domain decomposition
algorithm on a parallel computer. This parallel scheme will achieve
orders of magnitude reduction in computation times while making
full use of existing sequential algorithms for simulating periodic
systems on parallel computers. Perfect load balance will be
accomplished and inter-processor communication minimized using the
proposed scheme. Though the parallel algorithm is applicable to any
time-periodic system this effort will focus upon the rotor-stator
interaction problem using an existing highly accurate aeroelastic
analysis. By basing the analysis on a validated fluid-structure
interaction code, another drawback of existing rotor-stator codes
namely the absence of a true aeroelastic capability will be
repaired. In Phase I, validation exercises will be conducted on a
parallel machine in order to assess the coding effort entailed in
adapting an existing serial code to parallel computation and CPU
gains over serial methods using the proposed technique. In Phase
II. the technique will be extended to full 3D viscous aeroelastic
turbomachinery rotor-stator computations on a parallel machine.
The principal benefit of this work to commercial licensers of this
technology would be an order of magnitude reduction in computation
time for periodic problems involving viscous compressible
turbomachinery flows through the use of a novel time-decomposition
algorithm implemented upon a parallel architecture. The reduced
analysis time should open new design capabilities previously
considered unrealistic because of prohibitive computation cost and
help alleviate the costs involved in experimental testing of
turbomachinery designs.
Fluid/Structure Interaction, Parallel Computing, Time Domain
Decomposition, Low Communication Overhead, Transonic Flow,
Turbomachinery, Aeroelasticity
Project Title:
A Swirl Annular Combustor for Aircraft Gas Turbine Engines.
Advanced Projects Research Incorporated
147 Ward Street
Hightstown, NJ, 08520
93-1 01.02 4986 AMOUNT REQUESTED $70,000
A Swirl Annular Combustor for Aircraft Gas Turbine Engines.
Abstract:
This proposal describes an innovative Ultra-Low NOx annular swirl
combustor concept for aircraft gas turbine engines. The concept is
based on previously demonstrated means for creating high mixing
rate regions in free shear flows by manipulating existing vorticity
to create multiple discrete vortices in the flow. This mixing
technique coupled with a Lean-Burn Direct-Ignition (LBDI)
combustion strategy will be used in a high-performance low-loss
combustor design. This design addresses the aeropropulsion system
component need for innovative combustors with greater efficiency,
lower emissions, and reduced aerodynamic drag. The objectives of
the proposed Phase I project are to explore the combustor design
parameter space numerically and to demonstrate the feasibility of
the proposed concept experimentally. The results of the effort will
provide parametric data on the combustor geometry that will be used
in scaling the device to large annular systems for gas turbine
applications as well as a proof of principle demonstration. The
NASA applications and benefits include advanced ultra-low emission
combustors to address the needs for improvement in technology for
conventional subsonic aircraft and the high speed research program.
The commercial applications for the proposed technology lie in two
areas. First, the need and market for high performance combustors
for aircraft and industrial gas turbine engines is large. Second,
proposed technology will also be applied by Advanced Projects
Research Incorporated in a combustor for a gaseous waste
incinerator and ultimately in other commercial and industrial
burner applications.
Combustor, Low Emissions, Lean Burn Direct Ignition
Project Title:
An Advanced Wave Rotor Design for Low-NOx Turbine Engines
CFD Research Corp.
3325 Triana Blvd.
Huntsville, AL 35805
93-1 01.02 6576 __ AMOUNT REQUESTED $70,000
An Advanced Wave Rotor Design for Low-NOx Turbine Engines
Abstract:
A novel wave rotor topping cycle, which incorporates a Rich burn-
Quick mix-Lean burn (RQL) combustor integrally coupled with a wave
rotor, is proposed in this SBIR project. This cycle has the
potential of significantly lower NOx levels than demonstrated RQL
combustors, plus higher engine efficiency. In Phase 1, the
feasibility of producing a NOx emission index of less than 2 while
improving overall cycle efficiency will be evaluated using
analytical methods. Potential wavecycles and combustion systems
will be studied and promising designs will be selected based on
approximate wave-cycle analysis and emissions estimates. 2-D CFD
analysis of wave rotor flow will be performed to reveal important
flow phenomena and help select the best design. 3-D numerical
analysis of the combustor quick-mix section will be performed to
show the feasibility of low NOx levels. Allison Gas Turbine
Division, the selected sub-contractor, will assist in
review/assessment of the designs.
At the end of Phase I, the `best' wave cycle design and component
configuration will be recommended for Phase II study, which will
include both detailed simulation and experimental testing. If the
design is successfully demonstrated in Phase II, there will be
strong potential for application to new low-emission high
performance supersonic and advanced subsonic aircraft engines.
The final products of this project include: 1) a wave
rotor/combustor design that can be incorporated into a gas turbine
engine to advance performance and reduce emissions, and 2) a design
methodology for advanced low emission combustion and core engine
technology utilizing a wave rotor. These products are of growing
interest to manufacturers of gas turbine engines for supersonic,
advanced subsonic and industrial applications.
wave rotor, gas turbine, NOx, cycle efficiency, CFD, pressure
exchanger, emissions, combustor
Project Title:
Shape Memory Alloy Adaptive Control of Gas Turbine Engine Blade Tip
Memry Technologies, Inc.
57 Commerce Drive
Brookfield, CT 06804
93-1-01.02 7311 __ AMOUNT REQUESTED $69,637
Shape Memory Alloy Adaptive Control of Gas Turbine Engine Blade Tip
Clearance.
Abstract:
Blade tip clearance in a gas turbine is critical; each increment of
tip clearance reduction increases efficiency and reduces fuel
consumption. In this study only the compressor section will be
treated. Using a Lycoming T55L-712 turboshaft engine, which has
wide commercial and military application, two stages of the
compressor section will be modified to accept a shape memory alloy
ring whose inner diameter changes with temperature. The compensator
ring will be fabricated of an alloy whose transformation
temperature is suited to the stage 2 and stage 3 of this turbine,
and the design and thermo-mechanical processing of the ring will be
such that when the turbine has reached operating temperature, the
ring diametral change will reduce the tip clearance to
approximately 0.001". Performance will be evaluated for a range of
ambient air temperatures encountered, and the stability of the
compensator ring as a function of cycles of operation and dwell
time at operating temperature. The tip clearance compensation by
the shape memory induced diameter change of a ring insert would
substantially improve engine efficiency and fuel consumption.
Systems for accurately locating the rings in the shroud in both the
axial and radial direction will be developed as well as concepts to
facilitate assembly. Considerations will be given to extending the
concept to the entire compressor section.
An adaptive turbine tip clearance control requiring no external
power source offers efficiency improvement without impacting on
engine reliability or service life. Even small improvements in
specific fuel consumption have an economic impact. The
international market for gas turbines is large, and the competitive
position of U.S. turbine makers is aided by each increment of
improvement in performance.
Shape Memory Alloys, Turbine Tin Clearance Control
Project Title:
Optical Surface Contouring for Non-Destructive Inspection of Turbomachinery
Physical Research, Inc.
25500 Hawthorne Blvd., Suite 2300
Torrance, CA 90505-6828
93-101.03 0056 _ AMOUNT REQUESTED $70,000
Optical Surface Contouring for Non-Destructive Inspection of Turbomachinery
Abstract:
Detection and characterization of surface defects on the internal
components of propulsion systems is currently done by visual
inspection with borescopes. These inspections are subject to many
sources of error and uncertainty, making the experience of the
inspector a critical factor in the quality of the result. Current
economics pressures to improve competitiveness and efficiency exist
throughout the aerospace industry. Improved inspection techniques
are needed in order to eliminate unnecessary equipment teardowns
and yet protect safety margins while making better use of scarce
inspection expertise.
We propose to develop an instrument which will present to the
inspector an accurate three dimensional view of the surface under
inspection. This instrument will eliminate uncertainties about the
precise size of surface defects, making inspections quicker and
more accurate. The instrument will use the technology of non-
contact optical surface contouring; here applied for the first time
to an application which is so dominated by practical difficulties.
In phase I we will determine the feasibility of this instrument, in
both technical and practical terms. Our project team is uniquely
qualified; since it has strong capability in both electro-optical
instrumentation development in the commercialization of NDT
instrumentation for the aerospace industry.
The proposed inspection technology will lead to significant
improvement in the accuracy of inspection and safety of propulsion
system components. It will add significant capability of the in
service inspection of propulsion systems such as SSME turbopump
blades. Once developed, it will find immediate application in a
large variety of tasks where nondestructive, high accuracy
dimensional characterization of complex surfaces are required.
Non contact surface inspection, surface contouring, crack detection
Project Title:
Real Time NOx Measurement Using Spectroscopic Holography for Advanced Combustion Applications
MetroLaser
18006 Skypark Circle #108
Irvine, CA 92714-6428
93-101.03 0688 __ AMOUNT REQUESTED $69,960
Real Time NOx Measurement Using Spectroscopic Holography for Advanced Combustion Applications
Abstract:
This proposal details the necessary steps to adapt the newly
developed technique of Resonant -- Holographic Interferometric
Spectroscopy (RHIS), a powerful spectroscopic technique, to measure
NOx in real time at facilities such as the combustion test rigs at
NASA Lewis. RHIS combines the three-dimensional capabilities of
holography, the phase sensitivity of interferometry, and the
species selectivity of spectroscopy. State-of-the-art RHIS
instrumentation under development at MetroLaser is based on probing
with UV and visible lasers. The innovations in this proposal are to
extend the wavelength range of RHIS into the near IR, to provide
real-time data and to adapt the technique to measure NOx; an
important by-product of combustion linked to ozone depletion.
Extension of RHIS into the IR greatly increases its versatility
because the use of laser diodes dramatically reduces its
complexity, size, and expense. The main challenge for RHIS in the
IR is the lack of suitable holographic material. To meet this
challenge, significant effort will be devoted during Phase I to
examine nascent photorefractive materials for IR sensitive RHIS. In
addition to IR sensitivity, photorefractives require no development
processing, can be read in real-time, and are reusable.
If a Phase II program is funded, this work will result in the
development of an inexpensive, robust, lightweight device that
would have widespread applications in the areas of combustion
diagnostics, aerodynamic flow visualization and plasma deposition
monitoring/control as well as biological, medical and atmospheric
monitoring.
Holography, Nonlinear Optics, Spectroscopy, Interferometry
Photorefractive NOx Measurement
Project Title:
High Mobility Silicon Carbide Electronics
Advanced Technology Materials, Inc.
7 Commerce Drive
Danbury, CT 06810
93-101.03 1100 __ AMOUNT REQUESTED $ 70,000
High Mobility Silicon Carbide Electronics
Abstract:
Future aeropropulsion systems require high temperature electronics
and integrated sensors to meet desired performance levels. The wide
bandgap of silicon carbide (SiC) makes it ideally suited for high
temperature operation. To date, virtually all SiC-based devices
have been fabricated using 6H-SiC. Device performance would
significantly increase if 3C-SiC, the cubic form, were available.
3C-SiC has twice the electron and hole mobilities of 6H-SiC and a
slightly higher saturated electron drift velocity. Higher mobility
results in faster switching speeds, higher gain and lower on-
resistances. 3C-SiC is not typically grown in the bulk form because
it is not stable at typical sublimation growth temperatures. The
objective of this proposal is to grow high quality 3C-SiC. We
propose to do this through the development of a novel growth system
which will support the large thermal gradients required to
efficiently produce 3C-SiC. The anticipated results of this Phase
I will be the demonstration of a viable growth process for high
mobility 3C-SiC substrates. The benefits will be to make available
3C-SiC substrates and enable the manufacture of high performance
devices and sensors capable of operating in harsh, high temperature
environments.
The potential commercial products are high performance silicon
carbide devices and sensors which will be used in a wide range of
applications. These include monitor and control functions for high
temperature aeropropulsion and automotive applications and
electronic devices for generation and control of power, both at low
and high frequencies.
Silicon carbide, SiC, 3C-SiC, cubic SiC, high mobility
Project Title:
Intelligent Neural Control in Advanced Aeropropulsion Engines
Dynacs Engineering Co., Inc.
34650 US Hwy 19 N, Suite 301
Palm Harbor, FL 34684
93-101.03 4035 __ AMOUNT REQUESTED $ 69,684.00
Intelligent Neural Control in Advanced Aeropropulsion Engines
Abstract:
Dynacs Engineering Co., Inc. proposes the design and evaluation of
an intelligent neural control system in aerospace engines which is
capable of withstanding structural failures, component deviations,
and unpredictable perturbations. A hybrid connectionist system is
advocated to fulfill the critical needs in various operating
conditions. The motivation is to pursue a realization of a robust
and fault tolerant engine controller with a high degree of autonomy
and above acceptable performance. The particular areas that we will
address under the proposed efforts will include: identification-
dedicated and control-dedicated neural network architectures, real-
time learning rules, engine health component assessment, controller
association retrieval, and reconfigurable learning control. The
Phase 1 research objective is to demonstrate the proof of concept
of the proposed neural control approach through numerical
simulation of one segment of the overall engine control problem:
engine health component assessment for the Pratt & Whitney PW1128
engine model.
The proposed approach is applicable to space propulsion systems and
both military and civilian airbreathing propulsion systems. The
technology can be incorporated directly into various aerospace
engine control designs for civilian and military aircraft. In a
similar spirit, the proposed architecture can be extended to
dynamic control of large space structures, underwater vehicles,
chemical processes, power plants, and manufacturing scheduling. The
proposed technology will greatly reduce operational and
developmental costs and provide high performance, fault tolerant
control systems in various application domains.
Artificial Neural Networks, Reconfigurable Control, Fault Detection
and Identification, Aeropropulsion Control, Neural Control, Engine
Control, Intelligent Control
Project Title:
Noise Reduction System for General Aviation Aircraft
Ultramet
12173 Montague Street
Pacoima, CA 91331
93-101.04 0236 __ AMOUNT REQUESTED $ 70,000
Noise Reduction System for General Aviation Aircraft
Abstract:
Noise generated by general aviation aircraft has a negative impact
on the aviation community, and strict adherence to FAR Part 36
regulations requires noise reductions on the majority of these
aircraft. Any new aircraft certified or any modification to an
existing aircraft must show compliance with this regulation. The
majority of these aircraft are owned by individuals and are used
for recreational flying. Community airport noise standards are
increasingly more strict as suburban areas spread toward small
airports. The majority of noise in these airplanes, which use
reciprocating engines, is derived from the engine and exhaust, and
can be reduced or eliminated through the use of a properly designed
exhaust/muffler system. In this Phase I program, Ultramet proposes
to develop the design methodology and system characterization for
add-on muffler systems requiring only slight modification to the
exhaust system. A durable, high-temperature ceramic foam bulk
adsorber/baffle material will be used to create 20-25 dB engine
noise reduction at design exhaust system backpressures of less than
2" of mercury. The proposed program will include acoustic
characterization of various high-temperature baffle/adsorber
materials, providing a design methodology for a given airplane
engine noise frequency spectrum and sound pressure level.
Additionally, the design procedures and materials data will be
verified by constructing and beginning FAR qualification of a quiet
muffler system for a general aviation aircraft.
This program will provide the precompetitive design information
required to develop quiet mufflers and hush kits for general
aviation aircraft. Some 300,000 general aviation aircraft are
currently flying, all of which are or will be affected by community
airport noise standards as well as FAR Part 36 standards. Other
applications include motorcycle/moped, and performance automobile
mufflers.
noise reduction, general aviation aircraft, aircraft engines,
muffler, ceramic foam
Project Title:
Advanced Uniflow 2-Cycle Aero-Diesel Powerplant
G.S. Engineering and Machine Co.
P.O. Box 7743
Incline Village, Nevada 89450
93-1 01.04 3917 AMOUNT REQUESTED $67,850
Advanced Uniflow 2-Cycle Aero-Diesel Powerplant
Abstract:
This proposal outlines the design and development of a uniflow two
stroke Aero-Diesel engine core in response to the NASA SBIR
solicitation for a general aviation aircraft propulsion system.
The proposed engine will offer increased power density, simplified
operation, reduced emissions, noise, and vibration, while enhancing
reliability and safety when compared to currently available general
aviation aircraft engines. Important innovations are:
* Reciprocating, uniflow sleeve valve to control intake and
exhaust ports
* Hypocycloidal crank design that reduces engine size, weight
and vibration
* Electronic fuel injection/engine management system.
* Governor controlled single lever variable pitch integration
system. These innovations are aimed at the NASA supplied
objectives "to improve performance, safety and reliability,
simplify operations, reduce maintenance and costs, and improve
environmental compatibility." and address the limitations with
current general aviation powerplants.
Potential commercial applications of the proposed work are: 1)
UAV/RPV propulsion capable of running on heavy fuel, 2) small
marine engines for military, commercial, and recreational markets,
3) auxiliary power units (generators) and portable fire pumps, and
4) advanced, clean burning, two stroke diesel engines for
automotive and motorcycle markets.
hypocycloidal, sleeve valve, uniflow, diesel, two cycle, synergism,
lightweight, compound
Project Title:
Analysis/Design of Aeropropulsion Structures due to Acoustic and Dynamic Fatigue
Wright Materials Research
3591 Apple Grove Dr.
Beavercreek, OH 45430
93-1 01.05 4208 __ AMOUNT REQUESTED $ 69,995
Analysis/Design of Aeropropulsion Structures due to Acoustic and Dynamic Fatigue
Abstract:
Fatigue problem has been an important issue in aeropropulsion
system composite structures due to acoustic pressure, vibration and
hostile environments. Various forms of damage caused by fatigue
loadings can degrade the structural properties. This Phase I
research proposes a combined BEM/FEM approach (using 2-D and 3-D
elasticity theory) for dynamic analyses of aeropropulsion system
structures. The thicker part of the structure or the portion with
complex shape will be analyzed using a BEM whereas the thinner
section will be analyzed using a FEM. The new BEM proposed will be
able to accurately analyze anisotropic materials and structures
subjected to acoustic pressure and various forms of dynamic
loadings. The proposed methodology will capture the advantages of
both the FEMs and the BEMs and achieve an optimal combination of
efficiency, accuracy and cost. A user friendly computer program
with this BEM/FEM model and a fatigue criterion will be developed
for the probabilistic design of aeropropulsion system structures.
Dr. Tan and Dr. Li have published individually nearly forty papers
related to this topic. Once the computer program is parallelized in
phase II of this program it will be an excellent multidisciplinary
design and analysis tool for aeropropulsion system involving multi-
components.
The computational tool developed in this proposed program can be
used to effectively analyze and perform probabilistic design for
aeropropulsion composite structures including engine fan blade and
housing for military and commercial aircraft. When the computer
program is parallelized in Phase II of this program, the computer
execution time and cost will be reduced tremendously yet the
solution will be very accurate.
Aeropropulsion structures, Acoustic Fatigue, Dynamics,
Probabilistic Design, BEM-FEM
Project Title:
Structural Characterization of Metal-Matrix Composites Using Computed Tomography Data
ARACOR
425 Lakeside Drive
Sunnyvale, CA 94086
93-101.05 7780 __ AMOUNT REQUESTED $ 70,000
Structural Characterization of Metal-Matrix Composites Using Computed Tomography Data
Abstract:
ARACOR proposes to develop image processing tools and integrate
them into a software package running on UNIX workstations that can
efficiently and quantitatively analyze computed tomography (CT)
images of metal-matrix composites (MMC's). The software will
provide numerical data to microstructural and structural models of
performance. The Phase I effort will determine the relevant
features to be modeled in metal-matrix composites, determine
sensitivity of image processing tools to detect and quantify the
relevant features in MMC's, and develop a conceptual design of a
data analysis workstation for characterizing and quantifying MMC CT
data. It is anticipated that a software system can be designed
which will provide researchers with a user-friendly, efficient
system to extract relevant features from CT data of MMC's and
seamlessly integrate this data with existing modeling packages such
as finite element (FE) and computer-aided design (CAD) software.
The availability of such a software capability will transform CT
from a qualitative tool to a powerful quantitative tool which can
be used to test existing models, improve emerging models, and
develop new models to predict the structural performance of
aeropropulsion materials in complex, multivariable operating
environments.
A successful Phase II program will produce the software to
efficiently analyze nondestructive CT data of metal-matrix
composites specifically and many other material systems as well.
The software will be of significant use by researchers, developers,
designers, and users of advanced composite materials that have
access to CT data. The program will also produce the capability to
incorporate material databases with the software which will relate
CT data with mechanical properties. The databases thus provide
another avenue for commercialization.
Computed Tomography, Metal-Matrix Composites, Image Processing,
Quantitative Analysis, Workstation, Feature Extraction
Project Title:
Drag-Prediction Algorithms for Navier-Stokes Solutions over
High Technology Corporation
28 Research Drive
Hampton, VA 23666
93-1 02.01 0818B
Drag-Prediction Algorithms for Navier-Stokes Solutions over
Single- and Multiple-Element Airfoils
Abstract:
Accurate prediction of the aerodynamic lift and drag is a
critical requirement in the development process of an aircraft.
Presently, computational methods based on numerical solution of
the Reynolds-averaged Navier-Stokes (N-S) equations are being
applied by aircraft manufacturers to design aerodynamically more
efficient and structurally lighter and less complex multi-element
high-lift systems. Although these N-S solvers predict the complex
flow field and the lift force fairly well, the predicted drag is
often off by 100% or more. This discrepancy in the drag
prediction is in large part the result of calculating the
aerodynamic force using integration of surface pressure and
skin-friction distributions around the contours of the
configuration. The inadequacy of this "near-field" type of
drag-prediction technique has been known for more than fifty
years. However, present-day N-S solvers rely solely on this
technique to calculate drag, mainly because of its simple
implementation. In the proposed project several postprocessing
algorithms based on "far-field" type of drag-prediction
techniques will be developed and validated. These types of
techniques are known to be more accurate than the
surface-integration technique and will be applied to compute the
drag based on computed flow fields of various N-S solvers.
The proposed drag-prediction algorithms for Reynolds-averaged
Navier-Stokes solutions are unique and have direct commercial
value. Drag-prediction algorithms developed earlier by the
present investigators for inviscid flow (Euler) solutions are now
being implemented by the industry. The proposed computational
tools for viscous-flow solutions would further enhance the
efficiency of the aerodynamic design process of aerospace
vehicles.
computational fluid dynamics, postprocessing algorithms, drag
prediction, Navier-Stokes equations
Project Title:
Knowledge Driven Computational Fluid Dynamics Automation
ISX Corporation
4353 Park Terrace Drive
Westlake Village CA 91361
93-1 02.01 2020
Knowledge Driven Computational Fluid Dynamics Automation
Abstract:
This SBIR proposes to exploit the technical opportunity to apply
knowledge based systems (KBS) technology to increase the user
friendliness of Ames Computational Fluid Dynamics (CFD) numerical
aerodynamic simulations. Phase I has two objectives: establish
the feasibility of providing an innovative enhancement of the
user friendliness of surface, grid generation, and flow solver
application software through KBS technology; produce a system
design for a Phase II program developing a KBS enhanced CFD
capability. Five tasks are proposed to achieve these objectives:
CFD domain analysis; visionary system storyboarding; visionary
system design; technology assessment; Phase 11 development
roadmap construction. The Phase I program will result in a CFD
domain model and operational case, a process model and
operational scenario, a user validated storyboard demo, a
preliminary system architecture, a functional technology
requirement list, a technology assignment list, a critical
experiment list, and a Phase 11 development plan. KBS enhanced
CFD processes can provide an innovative means to assist Ames in
its mission to provide NASA with state-of-the-art numerical
aerodynamic simulation capability. The specific benefits will
include more frequent, wider, and higher quality use by air frame
designers (non-CFD staff) both inside NASA and in commercial
design organizations.
One of the largest user segments of Ames CFD capabilities is the
commercial aircraft industry. Although these users can be
sophisticated in aerodynamics, they may have little experience in
the nuances of numerical aerodynamic simulation. Improvements in
the user friendliness of Ames software would be of great interest
to this community and should lead to a range of commercialization
opportunities for software licensing and productization.
Computational Fluid Dynamics, User Friendly Systems, Expert
Systems, Knowledge Based Systems, Knowledge Engineering,
Associate Systems, Aerodynamic Simulation.
Project Title:
Error Analysis for Computational Fluid Dynamics
Creare Incorporated
P.O. Box 71
Hanover, NH 03755
93-1 02.01 3800
Error Analysis for Computational Fluid Dynamics
Abstract:
Present CFD software provides only crude or no estimates of
uncertainty in the calculated results. To bring error analysis in
CFD to the level of development achieved for experimental data
requires a systematic application of error analysis principles.
This project proposes to develop an error analysis methodology
and, if continued through Phase II, software to estimate
uncertainty in CFD calculations. The methodology will be
demonstrated in Phase I by CFD performance and uncertainty
calculations, comparisons with data, and a complete error
analysis for a basic problem of applied interest. The resulting
methods and algorithms will be applicable to a wide range of
other CFD problems.
The methods and software developed on this project will be
applicable to error analysis of CFD calculations for a wide
variety of government and industrial users of CFD.
computational fluid dynamics, uncertainty, error analysis
Project Title:
A Fully Conservative Chimera Approach for Structured/Unstructured
CFD Research Corp.
3325 Triana Blvd.
Huntsville, AL 35805
93-1 02.01 6576
A Fully Conservative Chimera Approach for Structured/Unstructured
Grids in Computational Fluid Dynamics
Abstract:
In the field of Computational Fluid Dynamics (CFD), a multi-zonal
approach greatly facilitates adequate representation of complex
geometry and different flow physics in different parts of the
flow domain. Previous multi-zonal patched and overlapped
approaches suffered from one or both of the following problems:
conservation and generality. A new approach is proposed to
resolve both of these problems. In the proposed approach, one of
the overlapping boundaries is used to divide the physical flow
domain into non-overlapping regions and flux conservation is
enforced on this overlapping boundary locally and globally. The
interpolation of flow variables from one zone to another is not
necessary. The proposed approach can handle overlapped structured
and unstructured grids, thus increasing its capability of
handling geometrically very complex components. The proposed
approach is fully conservative, suitable for both steady and
unsteady flow problems and easy to implement in
finite-difference/finite volume CFD codes. In Phase I, the
proposed methodology will be implemented and assessed for
selected 2D and 3D problems without relative mesh movement.
Further extension to viscous flows and unsteady flows with
relative mesh movement and implementation of the proposed
methodology in a production-level flow analysis code will be
carried out in Phase II.
The proposed project will provide a general, highly accurate,
fully conservative zonal interface method for arbitrarily aligned
structured/unstructured multi-zonal meshes. The stand alone
modules produced in Phase I can be easily integrated into
multi-zonal CFD codes, greatly enhancing their ability to handle
complex geometries with improved accuracy. The final adapted CFD
code, produced in Phase II, will have wide applications both in
Government and private industry.
Computational Fluid Dynamics, Conservative, Hybrid Grids,
Overlapped Grids, Chimera Scheme
Project Title:
Aeroelastic Navier-Stokes Code Using a Novel High Order Compact
Continuum Dynamics, Inc.
P.O. Box 3073
Princeton, NJ 08543-3073
93-1 02.01 9282
Aeroelastic Navier-Stokes Code Using a Novel High Order Compact
Scheme
Abstract:
A need to extend current second order accurate finite
volume-based flow solvers to higher order accuracy is identified.
To meet this goal, a higher order compact strategy for modeling
unsteady compressible and viscous flows is proposed. By forming
spatial moments of the applicative conservation laws and also the
k-e turbulence model equations, expressions governing the
evolution of the higher order spatial derivatives of the flow
variables are obtained. The higher order terms utilize the same
numerical flux-splitting expressions employed in their zeroth
order counterparts thereby taking advantage of the extensive
previous development of approximate Rieman solvers and also
retaining the closer physical modeling afforded by such models.
Different interpolation orders can be employed between
neighboring cells, thus opening the possibility of combined
polynomial order adaptation and spatial refinement leading to
faster convergence rates using fewer variables. During Phase I, a
2D aeroelastic Navier-Stokes code using a k-e turbulence model on
an unstructured triangular mesh will be developed. Results will
be obtained for selected transonic flows in order to validate the
code and demonstrate the computational effectiveness and
robustness of the higher order analysis.
The principal benefit of this work to commercial licensers of
this technology would be an adaptive higher order modeling
capability for fluid-structure interaction involving 3D
Navier-Stokes flows. Subsequent to the Phase I validation of the
new novel higher order compact scheme, an adaptive strategy
combining both polynomial order and spatial refinement will be
produced in the Phase II follow-on and applied to both fixed-wing
and rotor configurations. This software package will be marketed
in Phase III.
Higher Order Compact Scheme, Navier-Stokes Simulation, Finite
Volume Discretization, Fluid/Structure Interaction, Adaptation,
h-p Adaptation
Project Title:
Transition Control in Corner Flow of a Supersonic Square Nozzle
High Technology Corporation
28 Research Drive
Hampton, VA 23666
93-1 02.02 0818
Transition Control in Corner Flow of a Supersonic Square Nozzle
Abstract:
"Quiet" (low-disturbance) wind tunnels, needed for transition
research, require cleverly designed nozzle contours for
stabilization or delay of dominant instabilities in supersonic
nozzle wall boundary layers. However, if a nozzle of square
cross-section is utilized, nozzle performance may be degraded due
to early transition in flow along corners. Here, we propose a
study to understand the instability mechanism and evaluate
control techniques. "Quiet" supersonic nozzles are required for
research needed to develop aerotechnology for High Speed Civil
Transport (HSCT).
The proposed research will help develop such wind tunnel
facilities and will also have application in transition control
along the corners of the engine inlet for hypersonic transport.
The research is also relevant in wing-body juncture flows. Apart
from control techniques, a design-oriented computer code, which
will be of great commercial value, will result.
corner flow, transition, control, supersonic
Project Title:
Full Chord Laminar Flow for GA Aircraft Wings with only a Limited
Analytical Services & Materials, Inc
107 Research Drive
Hampton, VA 23666
93-1 02.02 7324
Full Chord Laminar Flow for GA Aircraft Wings with only a Limited
Suction Region
Abstract:
The perennial demand in the GA market for more speed can be met
without power increases by achieving extensive runs of laminar
flow. The use of full chord laminar flow can provide an eight
fold decrease in wing parasite drag and as much as a 35%
reduction in overall parasite drag for typical GA aircraft.
Laminarizing the wing surface of GA aircraft provides dramatic
drag reduction if 65% or more of the chord has been laminarized.
The use of suction limited only to a band within the aft pressure
recovery can stabilize the boundary layer of carefully designed
LFC airfoils and allow full chord laminar flow over the upper
surface including the flap region. The work team expertise has
been gained in a variety of state of the art laminar flow
research projects, as well as in the design of General Aviation
aircraft. The team's expertise has provided the NASA NLF(1)-0414F
that has demonstrated the lowest measured drag of any NLF
airfoil. The objective of the project is to design, as well as
develop, and build an airfoil and wing that can be conveniently
used on popular GA high performance aircraft. The ultimate goal
is to market the laminar flow wing as a series of FAA STCs for
re-winging a series of production GA aircraft.
The wing design proposed will find commercial applications in the
GA marketplace which has historically sought products that
provide an increase in cruising speed without requiring a change
in the powerplant.
Laminar Flow, boundary-layer, suction, wing, airfoil, aviation
Project Title:
New Models and Data for Nonequilibrium Chemistry in Hypersonic
CTSA, Inc.
140 Segsbury Rd.
Williamsville, NY 14221
93-1 02.03 0482
New Models and Data for Nonequilibrium Chemistry in Hypersonic
Flows
Abstract:
The development and validation of new theoretical models for the
rates of chemical reactions and molecular energy transfer are
proposed. The models will be valid for conditions of extreme
thermodynamic disequilibrium in hypersonic gas flows in which the
vibrational, rotational, and translational modes of molecular
motion are not equilibrated. Extension is also made to consider
energy transfer into low-lying excited electronic states. These
models will be incorporated into high temperatures compressible
flow codes, and can also be applied to new developing plasma
chemistry and laser technologies. The research will be done by
CTSA, Inc. with support from the Department of Mechanical
Engineering of The Ohio State University. The new rate models
will greatly improve the prediction of radiation, gas properties,
and thermal heating phenomena for flows around hypersonic
vehicles.
The nonequilibrium rate models to be developed are of crucial
importance to the design and analysis of electric discharges used
in new chemical syntheses (diamond films, stable isotope
enrichment) and for environment gas cleaning applications.
Aerothermodynamics, Nonequilibrium Flows, Molecular Energy
Transfer, Vibrational Relaxation
Project Title:
Deep-UV, Solid State Laser for Non-intrusive Diagnostics of
Schwartz Electro-Optics, Inc., Research Div.
45 Winthrop Street
Concord, MA 01742
93-1 02.03 2299
Deep-UV, Solid State Laser for Non-intrusive Diagnostics of
Hypersonic Flows
Abstract:
The innovation proposed here is the development of a new,
all-solid-state, single-frequency, laser that is tunable in the
180- to 210-nm region with application to hypersonic,
reactive-flow diagnostics. This wavelength region has not, to
date, been accessible with a practical laser that can provide the
performance characteristics needed for precision spectroscopic
techniques. In addition to providing a new, tunable laser source
in this region of the spectrum, the proposed approach will
provide an all-solid-state laser. The solid state design makes
the system intrinsically more suitable to use in laboratory
instrumentation overcoming a number of disadvantages posed by
other possible approaches that would employ non-solid-state media
such as excimers, organic dyes and gas cells. A practical laser
operating in this wavelength region will significantly enhance
the capabilities of spectroscopic techniques for hypersonic
reactive flows. Three techniques already identified as
beneficiaries are hydrogen RELIEF [1], high-brightness, O2,
RELIEF [1] and resonant holography [2]. The laser system is
comprised of four subsystems: 1) Nd:YAG pump lasers; 2) a
fixed-wavelength (1732-nm), Er:YLF, laser source; 3) a tunable
(205- to 240-nm), titanium-sapphire, laser source; and 4) the LBO
sum-frequency-mixing module where the 180- to 210-nm UV radiation
is generated.
The instrumentation developed under this program would have
applications as a commercial scientific laser system for use in
basic investigations of atomic, molecular, and radical species
that are not necessarily in high-speed flows. For example, it
would be useful in microgravity combustion diagnostics and in a
range of environmental remote-sensing applications where the
detection of specific species is critical.
tunable laser, non-intrusive diagnostics, hypersonic flows.
deep-UV laser
Project Title:
Imaging of Inlet Mass Capture in Hypersonic Engine Inlet Testing
Los Gatos Research
19148 Old Vineyard Rd.
Los Gatos, CA 95030
93-1 02.03 2310
Imaging of Inlet Mass Capture in Hypersonic Engine Inlet Testing
Abstract:
We propose to develop a new technology which will allow imaging
of the spatial distributions of air mass capture for testing and
development of advanced hypersonic engine inlets. The approach we
will develop will function within the constraints of the highly
limited optical access offered by such combustors and can offer
temporal resolution of better than five nanoseconds. The system
we will develop will be demonstrated in Phase I and installed and
tested on the 16 inch shock tube facility at NASA Ames Research
Center. At the present time, the 16 inch shock tunnel facility at
Ames is at the forefront of development testing for hypersonic
propulsion system design, and relies heavily upon computational
fluid dynamic code predictions to guide this work. Experimental
benchmark verification is desperately needed for this work to
continue on firm ground. The proposed work has significant
potential to provide such verification. Commercial applications
will be developed for flow imaging and fuel mixing optimization
in automotive and jet engine development.
This work will demonstrate a new technique which will permit two
dimensional imaging of flows under conditions of very limited
optical access. Commercial applications will be developed in fuel
and chemical mixing technology.
phase conjugation, laser sensing, imaging
Project Title:
A Simplified Vorticity-Enhanced Potential Flow Method for Early
Nielsen Engineering & Research, Inc.
526 Clyde Avenue
Mountain View, CA 94043-2212
93-1 02.05 9457A
A Simplified Vorticity-Enhanced Potential Flow Method for Early
Design and Analysis of Maneuvering Aircraft at High Angles of
Attack
Abstract:
Maneuvering aircraft at high angles of attack experience severe
unsteady loading. This loading, when unanticipated at the design
stage, can cause fatigue problems and, possibly, structural
failure. Such instances have occurred in the past, for example
on the twin vertical tail section of aircraft such as the F-15
and F-18, and may be anticipated with the F-22. The costs
associated with retrofitting such aircraft are substantial. If
the aerodynamic problems and/or fluid/structure interactions are
caught early in the design cycle, much of those costs can be
avoided. Preliminary design of high performance highly agile
flight vehicles requires efficient aerodynamic analysis tools.
These tools must be capable of capturing the key physics which
are the cause of these adverse interactions. For high angles of
attack and/or unsteady maneuver, the flowfield is complex and the
aerodynamic loads can no longer be characterized by simplified,
quasi-linear, methods such as aerodynamic derivatives. The
research work proposed herein is to develop a viable alternative
to existing methods by enhancing a well-tested three-dimensional
unsteady full potential code to include high angle of attack
vortical effects.
The proposed project is of considerable benefit to the Federal
Government and to the aerospace industry because the completed
Phase II project will deliver an engineering methodology and a
prediction tool to help designers to ensure that the fatigue
problems occurring on twin-tail tactical fighters do not arise in
future aircraft designs. The completed project provides the
basis for commercial software that will be licensed to the
aircraft and missile production companies to help their design
process.
Unsteady Aerodynamics, Unsteady Flow Separation, Vortex
Breakdown, Buffeting, Mathematical Modeling, High Angle of
Attack, Potential Flow, Computational Fluid Dynamics
Project Title:
An Optical Imaging and Tracking System for Rotor Blade Motion
Center for Remote Sensing, Inc.
5667 Snell Avenue, Suite 223
San Jose, CA 95123
93-1 02.06 9567
An Optical Imaging and Tracking System for Rotor Blade Motion
Abstract:
The advancement of modem helicopter designs is presently
dependent on the isolation and elimination of high level
vibration sources throughout the aircraft. One particular area of
concern is the rotor blades. The proposed research is directed at
designing and building a simple system for imaging and tracking
the complex rigid rotor blade motion of napping, lead-lag, and
blade pitch. This rotor blade imaging and tracking system will
provide an efficient and synergistic combination of a light
source that illuminates the rotor blades with a specific line
pattern, a camera assemblage for recording the reflected light
from the blades, and a software package to analyze the recorded
images and drive the tracking system according to desired
specifications. Tests with computer simulations and a model rotor
will demonstrate the feasibility of the imaging and tracking
system.
The optical rotor blade imaging and tracking system developed
here can be directly applied to commercial helicopters. The
system can also be adapted to other high-speed rotating devices
where design analysis of vibrations is critical. Examples are
turbines, rotating machinery, and aquatic and airplane
propellers.
Rotor Blade, Helicopter, Vibrations, Optical Tracking, Image
Processing
Project Title:
Active Suppression of Shear-Layer/Cavity Resonance Interactions
High Technology Corporation
28 Research Drive
Hampton, VA 23666
93-1 02.07 0818
Active Suppression of Shear-Layer/Cavity Resonance Interactions
Abstract:
The control of the resonant interaction between a free shear layer and an
open cavity is of direct relevance to wind-tunnel testing and aircraft
applications. Techniques will be investigated for the control of acoustic
resonances in open cavity flows. This problem is comprised of the nonlinear
interaction between a turbulent free shear layer, cavity acoustics, the
geometry of reattachment, and acoustic receptivity of the separating shear
layer. This program is focused on active minimization of acoustic levels
within open cavities, modification of shear-layer characteristics, and control
of complex feedback systems using neural nets. This approach is innovative
in the application of control strategies to shear layers with high Reynolds
number turbulent inflow conditions, the development of actuators, and the
application of neural nets to a system having multiple degrees of freedom,
multiple actuators, and minimization of acoustic levels over a large volume.
The effort is targeted at the control of turbulence-induced sound on models
and microphones, and is generally aimed at any flow separation problem with
resonance between a free shear layer and an open cavity, and the minimization
of noise in high Reynolds number open cavity flows as is encountered in
aircraft instrument bays.
Control of cavity acoustics and regions of flow separation on commercial
and military aircraft, modification of wind tunnel acoustics and low noise
microphone systems, ground vehicle source noise control, efficiency improvement
in combustors and combustion systems, and control of separation noise on submarines.
active control, cavity resonance, shear layers, neutral networks
Project Title:
Array Design for Wind Tunnel Acoustic Measurements
Planning Systems, Inc.
7923 Jones Branch Drive
McLean, VA 22102
93-1 02.07 3400
Array Design for Wind Tunnel Acoustic Measurements
Abstract:
We propose to determine the feasibility and the benefits of
making acoustic measurements in wind tunnels - such as the Ames
40-by-80 Foot Wind Tunnel using acoustic arrays. To prevent
acoustic path distortion due to the in-flow/ out-of-flow shear
layer, arrays must be placed in-flow. A major difficulty with
placement of sensors in-flow is self-noise. We propose as an
innovative solution to this problem the use of acoustic arrays
which reduce both ambient noise and self-noise. In particular,
we propose the use of Mills Cross arrays, which in addition
integrate out uncorrelated self-noise. Specifically, we propose
to determine the applicability of arrays by 1) analyzing
conventional and Mills Cross arrays of sensors, and 2) measuring
sensor self-noise characteristics, using innovative inexpensive
piezo-electric sensors developed by PSI for this purpose. Issues
such as potential array configuration, near-field vs. far-field
measurements, rejection of reflections, frequency coverage, and
robustness will be addressed. In the Phase I effort
computational, mechanical, and electrical specifications for the
proposed array and its signal processing will be produced. This
provides for a rapid implementation of improvements to the
measurement capabilities at Ames and other existing facilities.
Improved measurement capabilities for acoustic research in wind
tunnels is important to both the government and private sectors,
and both stand to gain from marketable advancements. This
project is a step toward providing a means by which existing
measurement facilities can achieve tangible improvement in
acoustic measurement capabilities, for a nominal cost. The
ensuing marketable products consist of specialized acoustic wind
tunnel arrays and processing systems.
Mills Cross, Arrays, Acoustic, Wind Tunnel, Piezo-electric Sensor
Project Title:
Microphone Arrays and Signal Processing for Accurate Wind Tunnel
Radix Systems, Inc.
6 Taft Court
Rockville, MD 20850
93-1 02.07 7410
Microphone Arrays and Signal Processing for Accurate Wind Tunnel
Acoustic Measurements
Abstract:
Existing legislation requires substantial reduction in the
radiated noise levels of commercial aircraft. Therefore, it is
especially important to obtain dependable acoustic measurements
of aircraft component models in wind tunnels before they are
incorporated into aircraft designs. The proposed method uses
microphone arrays to simultaneously focus upon the aircraft model
and to steer nulls at sources of interference, such as the wind
tunnel drive system or reflections from non-anechoic surfaces. To
adapt to the highly refractive wind tunnel conditions, a compact
sound source will be mounted on the model to emit periodic probe
pulses for direct measurement of propagation times. This
innovation will eliminate the need for detailed propagation
models, yet provide precise focusing and noise rejection. It will
improve signal-to-noise ratios, and yield accurate sound
radiation estimates of aircraft models in all wind conditions,
even in non-anechoic wind tunnels. Radix Systems, Inc. proposes a
complete series of microphone array designs and evaluations for
acoustic radiation measurements in the NASA Ames 40- by 80-ft
Wind Tunnel facility.
After a successful prototype demonstration in the NASA Ames Wind
Tunnel, development of microphone arrays and signal processors
for application in wind tunnels maintained by the major aircraft
manufacturers can proceed. The techniques to be developed are an
attractive alternative to expensive wind tunnel fan noise
quieting and acoustical wall treatments for eliminating
reverberation.
Broadband Radiation Measurement, Wind Tunnel Acoustics, Log-
Periodic Array, Null-Steer Beamforming
Project Title:
93-1 02.08 1122
A Novel, Non-Intrusive, Localized Gas Flow Diagnostic
This SBIR program will develop a novel optical diagnostic for
measuring velocity and turbulence in flowing gases. It is
non-intrusive, spatially localized in three dimensions, does not
depend on scattering from particulates or gas molecules and can
be absolutely calibrated. It is suitable for study of many
fluids, including hypersonic flows. The device measures optical
fluctuations due to gas density variations of selected scale size
in a small focal region within the flow. These fluctuations are
digitized at megahertz frequencies. The peak frequency in the
signal spectrum, combined with the spatial scale size setting,
directly determines the transverse flow velocity. Sound waves,
which show the local temperature, would produce additional
smaller spectral peaks. The scale size setting can be varied, or
several diagnostic heads can be combined to determine the
distribution of the turbulence scale sizes in the flow. The new
device will be demonstrated and characterized in Phase I and a
deliverable instrument will be designed to be built and used at a
NASA facility during Phase II.
This device will be simpler than hot-wire anemometry or laser
Doppler velocimetry and will measure additional flow parameters
as well. It can utilize any bright, collimated light source and
requires only two balanced photodetectors, making it potentially
inexpensive and therefore suitable for widespread use in fluid
studies.
flow, velocity, turbulence, fluctuation, correlation,
measurement, optical, wind tunnel
Science Research Laboratory, Inc.
15 Wart Street
Somerville, MA 02143
Abstract:
Project Title:
High Temp. Piezo and Ferroelectric Liquid Crystal Polymers for
Displaytech, Inc.
2200 Central Avenue
Boulder, CO 80301
93-1 02.08 8933
High Temp. Piezo and Ferroelectric Liquid Crystal Polymers for
Wind Tunnel Use Tunnel Applications
Abstract:
The optical visualization of air or gas flow and the induced
stress field is crucial to many applications in aerodynamic
research. A new liquid crystal shear sensor based on
ferroelectric liquid crystals has been shown to respond in the
sub-millisecond time regime, making it an attractive candidate
for a fast response flow-field sensor. Two drawbacks are noted
for use of FLCs as field-flow sensors: 1) the active temperature
range of a typical FLC is usually below 100@C, and 2) due to low
viscosity, high air flows tend to remove the liquid crystal from
the test surface. In this proposal, we suggest an approach that
should dramatically improve performance of FLCs in both these
areas. By attachment of the properly selected FLC mesogen to a
polymer backbone, the smectic C range can be greatly raised, and
adhesion to the test surface markedly improved. In addition,
integration of high polarization mesogens should result in a
strong piezoelectric effect useful in pressure sensing
applications.
The new shear stress and pressure sensors can be used in
communications, medical instrumentation, mechanical field
measurements, and aircraft safety and design.
ferroelectric, FLC, piezoelectric, pressure sensor, field-flow
sensor
Project Title:
High-Speed Optically Buffered Flow Visualization System
Innovation Associates, Inc.
P.O. Box 1306
Ann Arbor, MI 48106
93-1 02.08 9338
High-Speed Optically Buffered Flow Visualization System
Abstract:
Fast framing digital cameras which can acquire high spatial
resolution transient wind tunnel flow-visualization imagery in
boundary layers do not yet exist. To address this need,
Innovation Associates proposes to develop a unique High-speed
Optically Buffered Flow-Field Visualization System (HOBS)
utilizing recently developed real-time holographic recording
media such as bacteriorhodopsin. HOBS will be capable of: a)
recording 100 2-D flow visualization images with 512x512
resolution at a 10k or higher framing rate onto an optical
buffer, b) re-imaging and digitizing the stored images at
standard video rates, and c) storing the digital images onto a
computer disk for subsequent analysis. No other global flowfield
visualization technique presently exists which can rapidly
provide digitized images with the speed of resolution of HOBS.
During Phase I, Innovation Associates will demonstrate the
feasibility of developing the optical buffer utilizing recently
developed high-resolution real-time recording media, will
evaluate options for extending HOBS design to support higher
framing rates and larger number of recorded images, and develop
the system design and specifications for Phase II implementation.
The proposed system will provide an advanced research and
inspection tool for laser-materials interaction, plume evolution,
shock waves, hypervelocity ballistics detonations, plasma
evolution and any process requiring high speed photographic
system.
wave-front, wave-front analysis sensor, interferometry, high
speed videography, bacteriorhodopsin, photo-polymer
Project Title:
Development of a Finite Element Model of Elastic Porous Materials
Automated Analysis Corporation
2805 S. Industrial, Suite 100
Ann Arbor, MI 48104-6767
93-1 02.09 1000
Development of a Finite Element Model of Elastic Porous Materials
for Use in Passive and Active Noise Control Design Procedures
Abstract:
In the proposed work a complete elastic porous material theory
will be used as a basis for developing the first two-dimensional
acoustical finite element model of noise control foams. Although
foams are widely used for passive control of aircraft and
automobile interior noise, complete numerical models of those
materials do not exist, thus limiting the design alternatives
available to numerical analysts. The development of finite
element foam models that are compatible with existing acoustical
finite element codes would allow, for example, optimal design of
high transmission loss fuselage treatments by using modern
numerical techniques. To illustrate the utility of the proposed
work, the transmission loss of finite, foam-lined fuselage
sections will be calculated. In addition, a two-dimensional
acoustical finite element model of "smart foam" will be
developed, so allowing simulations of the latter's effectiveness
for active control of vehicle interior noise. "Smart foams" are
foam layers containing shaped piezoelectric membranes; by
applying appropriate voltages to the membrane it may be possible
to enhance the sound absorption and transmission properties of
foam layers, particularly at low frequencies. The work will be
performed over a period of six months by AAC personnel with
assistance from personnel at Purdue University.
The elastic-absorption finite element technology developed during
Phase I ca be marketed as a complement to the general purpose FEM
code that is currently being developed by Automated Analysis
Corporation. It is also a valuable addition to established
general purpose acoustic codes. It will promote active and
passive noise control researches in the aerospace, automotive and
defense industries.
Finite Element Model, Elastic Porous Material, "Smart Foams"
Project Title:
Prediction of High Speed Jet Noise Reduction by Vorticity Shed
BEAM Engineering and Applied Research
612 E. Buffalo St.
Ithaca, N.Y. 14850
93-1 02.09 1724
Prediction of High Speed Jet Noise Reduction by Vorticity Shed
from Circumferentially Mounted Elements
Abstract:
We will develop a method to predict the increase of mixing in a
high speed jet by vorticity shed from elements mounted on the
circumference of the jet lip. In high speed jets the increase of
mixing is directly correlated with noise reduction. Noise
reduction, in turn, is an important goal of the NASA High Speed
Research Program. Recent experiments at NASA Langley have shown
that a ring of circumferentially mounted prism shaped wedges
protruding into the jet reduces the noise emitted. The end
product of this work will be a tool to optimize the shape and
spacing of the circumferentially mounted elements, to this end we
will develop a method to estimate the increase in mixing. The key
ingredients in the prediction of the increase in mixing are: A
quantitative model for the vorticity shed from the particular
shape mounted on the jet circumference; A model for the evolution
of the vorticies shed as they are swept downstream; An estimate
of the likelihood and location of vortex breakdown; An evaluation
of the total increase in mixing in the jet mixing layer; A study
of the stability of the annular mixing layer with respect to
three dimensional perturbations and the possible development of
three dimensional jet instability modes. In Phase I we will
concentrate on a particular shape for the elements, namely the
prism shaped elements for which noise reduction experimental data
from a hot high speed jet is available for comparison. In Phase
II we will develop a complete design tool for optimizing the
shape and spacing of the elements for the purposes of increasing
the mixing in the jet annular mixing layer or jet noise
reduction.
The tool will be used in the design of engine nozzles for the
High Speed Civil Transport, where noise reduction is a critical
issue. The design tool offers great savings over experiments that
attempt to map out the effects of shape and spacing on the
increase of mixing and noise reduction. Other applications which
benefit from increased jet mixing in the areas of combustion and
civil engineering offer additional commercial potential.
High Speed Jets, Noise Reduction, Increase Mixing
Project Title:
Supersonic Jet Noise Prediction and Control
High Technology Corporation
28 Research Drive
Hampton, VA 23666
93-1 02.10 0818
Supersonic Jet Noise Prediction and Control
Abstract:
Recent studies have demonstrated that a definite relation exists
between instability waves and noise of high-speed jets and,
hence, the instability wave model can be used to predict certain
features of the jet noise. The instability model used in these
studies is based upon compressible Rayleigh equation. Here, we
propose to develop a computer code which will incorporate a much
more advanced stability model based upon full nonlinear equations
for a developing jet. This new nonlinear instability model can
provide an efficient means for performing control studies using
nozzle geometry, jet temperature, swirl and modal interaction.
The proposed model can not only provide qualitative features of
the jet noise but also will predict its amplitude and can also be
used to compute Lighthill's stress tensor. It will serve as a
bridge between the simplistic approach based upon compressible
Rayleigh equation and the direct solution of the Navier-Stokes
equations. Computationally, the proposed approach is two orders
of magnitude cheaper than DNS and, therefore, it constitutes a
viable design approach.
Control of jet noise has many commercial applications and is of
particular relevance to High Speed Civil Transport (HSCT). The
computer code developed under the proposed project can be used by
engine companies in their design studies and, therefore, is of
commercial value.
jet noise, nonlinear, instability waves, control
Project Title:
THE USE OF COWL CAMBER AND TAPER TO REDUCE ROTOR/STATOR
Cambridge Acoustical Associates, Inc
200 Boston Avenue, Suite 2500
Medford, Massachusetts 02155
93-1 02.10 1421
THE USE OF COWL CAMBER AND TAPER TO REDUCE ROTOR/STATOR
INTERACTION NOISE
Abstract:
The primary aims of the proposed research are: (1) To develop a
sophisticated numerical model to explore the effects of cowl
shape on the diffraction of the noise from rotors and stators;
(2) to similarly predict the dissipative effects on net exterior
noise of the fore/aft taper and geometric layout of the cowl's
interior liner; (3) to exploit the theoretical variability of
both features simultaneously, i.e., as two rigorously coupled
diffractive and dissipative systems, in order to maximize the
overall acoustic shielding provided by a given cambered/tapered
design. The speed range will be high subsonic and the frequency
range will be greatly noncompact for the cowl as a "ring wing"
(both requirements following from NASA's own practical interests
in present and future commercial aviation). An important sideline
of the work will be to produce a realistic theoretical model of
the rotor/stator insonifying system. Rotor/stator interactions
will be for twisted blades of arbitrarily wide chords.
The proposed research will produce a computer code that will
assist the design of quieter ducted propulsion systems for the
next generation of commercial aircraft engines.
Camber Effects, Ducted propeller, Aeroacoustic scattering
Project Title:
Vortex Flap Improvements for Enhanced Low-Speed Aerodynamics of
ViGYAN, Inc.
30 Research Drive
Hampton, VA 23666-1325
93-1 02.11 1400
Vortex Flap Improvements for Enhanced Low-Speed Aerodynamics of
Supersonic-Cruise Aircraft
Abstract:
Leading edge vortex flap modifications are proposed for improved
low-speed lift and L/D characteristics of supersonic cruise
aircraft. The aim is to increase the vortex-lift potential in
addition to generating vortex thrust on highly-swept wing
configurations, thus enhancing the low-alpha lift, aerodynamic
efficiency and noise reduction of highly-swept aircraft
configurations during take off, climb-to-cruise and landing
approach, in comparison with the inboard-hinged leading edge
flaps of current practice. Low-speed wind tunnel tests will be
performed for a comparative evaluation of the different vortex
flaps on a common, generic slender-wing planform. Flow
visualization diagnostics will also be conducted to characterize
the unique vortical features of the modified flap configurations.
The results will quantify the performance increments realizable
from the proposed modifications, and also provide insights
enabling more refined vortex management techniques for
slender-wing lift enhancement and drag reduction. Successful
outcome of this work will directly benefit current NASA research
directed towards a quieter next generation supersonic civil
transport.
The technology objective and outcome of this research will be of
considerable interest to U.S. Aircraft industry engaged in the
design of nextgeneration civil and military supersonic vehicles,
by enabling reductions in field-length requirements and noise
levels associated with take off and landing of high-performance
aircraft.
Supersonic Aircraft; Low Speed Lift; Induced Drag; Vortex Flaps;
Leading Edge Devices; and Wind Tunnel Test
Project Title:
A Personal Computer Aided Design System for General Aviation
Design, Analysis and Research Corporation
120 East Ninth Street, Suite 2
Lawrence, KS 66044
93-1 02.12 0434
A Personal Computer Aided Design System for General Aviation
Aircraft Configurations
Abstract:
A personal computer based preliminary design system for General
Aviation aircraft will demonstrate a practical method to design
and analyze general aviation aircraft configurations. The program
will provide a powerful framework to support the non-unique
process of aircraft preliminary design. The system will allow
design engineers to rapidly evolve an aircraft configuration from
weight sizing through detailed performance calculations, while
working within regulatory constraints. The program will be
designed to reduce the preliminary design phase cost and to bring
advanced design methods to businesses which normally do not have
the computational and/or modern design/analysis capability.
Decrease design cost for small aircraft manufacturers. Enhance
educational process at universities for aircraft design. Improve
competitiveness for small aircraft manufacturers.
aircraft preliminary design, design system, aircraft
configuration
analysis
Project Title:
A User-Friendly Expert System for Airfoil Design and Boundary
Innovative Aerodynamic Technologies
417 Whispering Pine Drive
Grafton, VA 232692
93-1 02.12 7324
A User-Friendly Expert System for Airfoil Design and Boundary
Layer Stability Analysis
Abstract:
The quest for performance, fuel efficiency, range and speed in
the current global economic environment, has sparked a renewed
interest in designing and analyzing lamianar flow wings for
airplanes. Currently, the capability to design and analyze
laminar flow wings only exists at large commercial aircraft
companies and government research organizations. These stability
analysis methods currently require "expert" input choices, as
well as "expert" interpretation of the results. The innovation
proposed is to develop a user friendly graphical user interface
(GUI) based laminar flow analysis system. This system will
integrate a flow analysis solver, a boundary layer-mean flow code
and a stability analysis code into an icon based control program.
Expert input provided by the development team's experience will
be coded into the control program's database. The value of this
practical application program development is that applied
aerodynamicists will finally have a laminar flow airfoil design
and analysis tool. The commercialization of this application
software to applied engineers in GA, universities and other
industries will be invaluable, and act as a catalyst for
designing the next generation of advanced high performance
aircraft.
The user-friendly expert stability analysis system will find a
market place in numerous establishments conducting NLF or LFC
airfoil/wing design. Possible users are GA companies of both
certified and experimental aircraft, universities for
aerodynamics students and engineers at large commercial aircraft
companies. Individuals interested in wing design can use the PC
based version.
Laminar flow, boundary layer stability, NLF/LFC airfoils
Project Title:
A Robust Aerodynamic Analysis Method for Design of General
Desktop Aeronautics
P.O. Box A-L
Stanford, CA 94309
93-1 02.12 8588
A Robust Aerodynamic Analysis Method for Design of General
Aviation Aircraft Configurations
Abstract:
This proposal deals with an innovative approach to the
aerodynamic design of subsonic aircraft, permitting more rapid
evaluation of configurations at the early stages of the design
process, and enabling preliminary design refinement and
optimization. The proposed work involves the development of a
practical computational method for aerodynamic design, based on
the offerer's widely-used interactive design software. The new
method permits rapid computation of three-dimensional lifting
surface aerodynamics, avoiding anomalous results that often arise
from panel spacing sensitivity in conventional programs. The
approach is based on the interpolation schemes developed for
vortex-in-cell methods, but retains the computational efficiency
of linear methods. In Phase I of this SBIR effort, a pilot code
demonstrating the feasibility, efficiency, and robustness of the
new method will be developed. If successful, the methodology may
form the basis for a new commercial software product and/or may
be incorporated into codes currently used by NASA or industry.
The approach is especially relevant to general aviation design:
its robust, rapid turn-around character makes it well-suited for
use by individuals with limited computer resources, or for
configuration optimization of interfering systems such as
3-surface designs, canards, or winglets.
If the approach is successful it would lead to a commercial
software product to be developed by the offeror in Phase II. The
technology could be incorporated into numerous, existing
commercial and government codes. Such programs would aid general
aviation manufacturers in initial design and development of
either conventional or innovative configurations.
Aerodynamics Optimization Design
Project Title:
LOW COST ELECTROMAGNETIC DEICE FOR NATURAL LAMINAR FLOW AIRFOILS IN
CIRRUS DESIGN
S. 3440 A HWY 12
BARABOO, WI 53913
93-1 03.01 2266 Amount Requested $ 70,000
LOW COST ELECTROMAGNETIC DEICE FOR NATURAL LAMINAR FLOW AIRFOILS IN
GENERAL AVIATION APPLICATIONS
Abstract:
Cirrus Design proposes the development of a low cost,
electromagnetic-type deice system that is integrable with Natural
Laminar Flow (NLF) airfoils, on General Aviation (GA) aircraft. To
compete with alternate modes of travel like the interstate highway
system and airlines, GA aircraft must provide transportation that
is fast, economical, safe, and reliably usable in any weather. The
operation of light personal transportation aircraft of the near
future will be made economically viable by the application of NASA
developed technologies. The NLF airfoil series is an important
example of those technologies. With very low drag coefficients at
cruise speeds, it makes possible single engine aircraft that
provide truly rapid personal transit. Electromagnetic type deicing
is another example of a NASA developed technology that will soon be
important to the utility of small single engine aircraft.
Electromagnetic techniques provide deicing systems that are light
weight, relatively low cost, and require relatively low power for
actuation. Deicing systems currently available, are either too
expensive for small business and personal transportation aircraft,
or are not built to maintain natural laminar flow. The development
of an NLF compatible, electromagnetic deice system will be a
significant step in making GA travel safer and more dependable.
General aviation aircraft sales reached 18,000 new aircraft per
year in the late 1970's before dropping off to what it is today.
The need for personal aviation transportation is still there, but
the market (particularly business) now demands cost effective
travel that is reliable and safe to operate in all weather
conditions. Small single engine aircraft, NLF airfoils, and
reliable deicing is the only combination that can meet that demand.
ELECTROMAGNETIC DEICE, NATURAL LAMINAR FLOW, GENERAL AVIATION
Project Title:
ANTI-ICING OF GAS TURBINE ENGINE INLETS
Thermacore
780 Eden Road
Lancaster, PA 17601
93-103.01 6551 __ AMOUNT REQUESTED $ 69,987
ANTI-ICING OF GAS TURBINE ENGINE INLETS
Abstract:
In turboshaft and turbofan gas turbine engines, anti-icing of the
cowl currently uses compressor discharge bleed air. Use of this air
decreases the net thrust or shaft horsepower, and increases the
fuel consumption. This proposal contains an innovative loop pipe
method to eliminate the use of bleed air for anti-icing of the
turbine engine inlet. Engine cycle analyses predict an increase in
shaft horsepower of up to 5% combined with a 5% fuel reduction for
an IHPTET Phase II turboshaft engine at 20% Maximum Continuous
Power (MCP). Loop pipes are similar to heat pipes, however, loop
pipes are self-priming during start-up, significantly increasing
reliability. In addition, loop pipes are more easily designed to
operate in the turbine engine environment, with its high
maneuvering accelerations.
Loop heat pipes have already been fabricated with power and
gravitational heads that are similar to the anti-icing
requirements. The Phase I program objective is to examine two
aspects of loop pipes that have not previously been addressed: (1)
The ability to turn the loop heat pipe off and on, and (2) the
ability to restart against high accelerations.
This innovative anti-icing method will be directly applicable to
commercial turboshaft and turbofan engines, increasing net power
and the power-to-weight ratio, while decreasing fuel consumption.
The benefits are highest at the low power point. The most dangerous
icing conditions typically occur while an aircraft is in low-
altitude holding pattern prior to landing. By eliminating the high
percentage bleed currently required for anti-icing aircraft safety
will be increased.
Anti-Icing, Gas Turbine Engines, Heat Pipes, Loop Heat Pipes
Project Title:
Aircraft VHF Lightning Detector of Weather Hazards
Airborne Research Associates
46 Kendal Common Road
Weston, MA 02193
93-1 03.02 1834 __ AMOUNT REQUESTED $ 70,000
Aircraft VHF Lightning Detector of Weather Hazards
Abstract:
This proposal is for development of an aircraft VHF lightning
detection system capable of determining the location of intracloud
(IC) as well as cloud-to-ground (CG) lightning. While lightning is
hazardous in itself it also marks regions with hail, severe
turbulence, and heavy rain. In addition, IC lightning appears to be
useful for predicting microbursts and subsequent windshear which is
a major hazard to aviation. Accurate lightning location from
aircraft has not been possible in the past using existing VLF
systems. VHF instrumentation will be used for detecting IC
lightning with the required spatial resolution to relate its
position to regions with hazardous weather. A novel method for
determining the distance to lightning will utilize the difference
in time-of-arrival between the direct signal and the signal
reflected from the Earth's surface. The prototype system will be
tested from an aircraft in the Orlando-Kennedy Space Center region
of Florida where ground based instruments can map the IC lightning
as well as windshear. A graphic display will allow pilots to avoid
hazardous regions. Preliminary studies indicate the proposed system
should perform as anticipated.
An IC lightning detector for thunderstorm avoidance has a potential
market of about 100,000 aircraft. Most are single engine and have
no suitable location for a radar antenna. The possibility of
locating regions where windshear might occur also should be of
considerable interest to the airlines since there is no other
technology capable of predicting windshear minutes in advance.
weather, lightning, microburst, windshear, thunderstorm
Project Title:
Aircraft Wake Tracking, Analysis and Algorithm Development
Coherent Technologies, Inc.
P.O. Box 7488
Boulder, CO 80306-7488
93-1 03.02 8736 Amount Requested $ 69,116
Aircraft Wake Tracking, Analysis and Algorithm Development
Abstract:
NASA has recently begun a program to improve terminal area
productivity (capacity) that will serve to simultaneously save
airline operating costs and improve aviation safety. Reduction of
aircraft spacing during instrument flight rules (IFR) conditions
requires a thorough understanding of environmental effects on wake
vortex transport and decay mechanisms. In the proposed program,
existing algorithms for processing coherent lidar data to locate
and track aircraft wake vortices and to display the wake structure
are to be expanded. A currently available database of wake
measurements made at Stapleton International Airport will be
analyzed with existing algorithms for wake tracks and wake
strengths. Tracks will be correlated with available environmental
data and analyzed for wake decay and transport mechanisms. A 2D
Kalman hydro-code analysis will be upgraded and applied to these
data and the results assessed for capability of the Kalman
procedure to identify wake structure. An analysis of the
requirements for implementation in 3D with a high PRF system will
be developed and incorporated into the existing real-time processor
using a limited 3D grid and evaluated for capability to handle an
upgrade to a high PRF. Memory and CPU requirements for a 3D
implementation of the Kalman analysis will be determined and a
design for an upgraded real-time processor will be developed.
The proposed development of algorithms and an advanced real-time
processor will support a wide range of applications. Applications
include: ground-based airport scanning systems for windshear and
vortex wake applications; various on-board sensing scenarios,
including detection of trailing vortices; airdata applications
involving wind vector data acquisition; and processing for
autopilot input and flight control during clear-air turbulence or
wake vortex encounters.
lidar, laser radar, coherent detection, wake vortex
Project Title:
Automated Nap-of-the-Earth Data Collection Radar Definition
Technology Service Corporation
2950 31st Street
Santa Monica, CA 90405
93-103.04 9755 __ AMOUNT REQUESTED $
Automated Nap-of-the-Earth Data Collection Radar Definition
Abstract:
Nap-of-the-Earth (NOE) flight in a conventional helicopter is
extremely taxing for two pilots under visual flight rules (VFR)
conditions. There is a desire to develop an all-weather Automated
NOE (ANOE) system that will allow a single pilot to safely fly a
helicopter at altitudes near 50 feet. Recent work by NASA/ARC has
indicated that ranging to the ground and potential hazards using
passive camera sensors can significantly improve ANOE performance.
These sensors indicate that an effective all-weather, day/night,
ANOE system can be developed by augmenting passive sensors, INS/GPS
and hazard data with an active radar system. At present, the data
base required to specify such a sensor system does not exist.
This proposal is to define a low cost, data collection radar to
derive the necessary data base. During Phase II the radar would be
developed and tested. This radar will collect data not only for the
ANOE mission but will also collect data to determine its utility as
a situational awareness sensor during approach, landing and
taxiing. In addition, the radar will collect preliminary data to
help define a machine vision system for landing in very low
visibility.
The critical issues are height measurement accuracy and hazard
detection, e.g., towers and wires. We will use our experience in
developing unique algorithms for obtaining very precise height
accuracy. We will use elevation and azimuth monopulse diversity to
detect and measure hazardous obstacles.
If an ANOE system can be developed using an active radar, the
commercial applications are myriad. The system would be extremely
useful to law enforcement helicopters when searching for a fugitive
or tracking a vehicle. News organizations who use helicopters will
also use the system. Other potential users include crop dusters,
remote sensing aircraft and helicopters, especially those used for
below ground surveillance, rescue helicopters, forest fire chemical
and water dropping, air vehicles etc.
Nap-of-the-Earth, Terrain Avoidance, Radar, Terrain Following,
Hazard Detection, Data Fusion
Project Title:
Compact, Airborne, Particle Sizing Sensor
MetroLaser
18006 Skypark Circle #108
Irvine, CA 92714-6428
93-103.05 0688 __ AMOUNT REQUESTED $ 69,962
Compact, Airborne, Particle Sizing Sensor
Abstract:
A unique, airborne particle sizing system is proposed to reliably
measure the size and number of particles found in the atmosphere
from their backscattering off-axis signal. The proposed technique
will solve a fundamental problem in optical particle sizing that
normally prevents the use of backscattering or near backscattering.
Multiple wavelengths from independent laser diode sources will be
mixed to produce a laser sheet to illuminate the particles. Light
scattered at angles between ninety degrees and backscattering by
particles crossing the laser sheet will not have the large Mie
scattering oscillations characteristic of monochromatic radiation,
but instead will be characterized by a near-monotonic distribution.
The feasibility of using two receivers positioned symmetrically to
the laser transmitter will be explored to assess the ability of
establishing particle asphericity. A backscattering receiver with
an interference filter centered at a wavelength of interest to
optical air data systems will provide the backscattering
distribution. Analyses using five discrete wavelengths near 800 nm
show that particles between 0.4 æm and 20 æm yield a typical
measurement error of 5% for known index of refraction. Phase I will
include analytical studies and experimental work with particles of
known size and composition.
The commercial application of this research is based on the
development of a backscattering instrument to characterize the size
distribution of airborne particles such as those found in the
atmosphere, dusty flows, and sprays. This instrument will overcome
the limitations of existing, commercially available forward
scattering systems.
Particle size, airborne, optical fibers, multiple wavelengths
Project Title:
A REAL-TIME REMOTE-SENSING AIR TEMPERATURE RADIOMETER FOR HIGH-
OPHIR Corporation
10184 West Belleview Avenue, Suite 200
Littleton, CO 80127
93-1 03.05 2200 Amount Requested $ 69,879
A REAL-TIME REMOTE-SENSING AIR TEMPERATURE RADIOMETER FOR HIGH-
SPEED AIRCRAFT
Abstract:
We propose to develop a novel radiometer for real-time
measurements of atmospheric air temperature from high-altitude, high-speed
aircraft. As stated in Topic Number 3.05, NASA requires airborne
atmospheric air temperature measurements to assist the evaluation
of current and developing aerospace vehicle performance.
Presently, accurate real-time measurements of atmospheric
temperature cannot be performed from high-altitude, high-speed
aircraft. And yet, air temperature is a fundamental atmospheric
parameter influencing the aircraft's performance. Atmospheric
temperature is used to determine aircraft airspeed and local air
density. Atmospheric temperature affects jet engine performance
and can be used during the estimation of optimal power settings
and fuel consumption.
The proposed technique is not adversely affected by dynamic air
heating, which renders conventional immersion sensors useless at
high aircraft speeds. Proposed innovations will enable a highly
accurate and reliable sensor to be developed as a small, light
weight, instrument suitable for airborne applications.
The proposed effort will determine the feasibility of this
technique for high-altitude, high-speed aircraft. A preliminary
hardware design will be completed to provide an accurate
assessment of the estimated sensor performance. If successful, these
efforts will enable a prototype sensor to be fabricated, calibrated, and
flight-tested in Phase II.
The primary benefit of this research will be the development of
an un-obtrusive, remotesensing thermometer for high-speed aircraft.
Since no accurate means of determining air temperature from such
aircraft presently exits, this technology hold considerable
commercial potential for both civilian and military aviation. This
technology also hold commercial potential as an airborne
thermometer for meteorological research applications.
remote sensing, radiometer, air temperature, high-speed
Project Title:
Thin Film Pressure Sensor with Optical Output
GRE Incorporated
P.O. Box 30863
Albuquerque, NM 87190-0863
93-1-03.05-8277 __ AMOUNT REQUESTED $ 69,801
Thin Film Pressure Sensor with Optical Output
Abstract:
We propose a thin, flexible pressure sensing film with optical out-
put consisting of a polymer LED on a piezoelectric polymer
substrate. The innovation lies in combining these two types of
polymers to make a single sensor which will provide a minimal
intrusion method for measuring pressure distributions on structures
in free-flight and/or wind tunnel tests. Spatial resolution should
be better than 1 mm. Response times could be as short as 1 æs.
Power consumption could be as low as a few Wm-2. The project
objectives are to show that the device can be fabricated, to show
that it functions as anticipated, and to develop a conceptual
design for a sensor to be demonstrated in wind tunnel tests. The
effort proposed is about 6 man months including subcontractors (for
device fabrication) and a consultant (in design and applications).
We anticipate that the objectives will be met and that a
demonstration in a wind tunnel will be possible in Phase II. Phase
III would include manufacturing of sensors for use in NASA
aerodynamic testing. These sensors will improve understanding of
flow features and will lead to design of more capable and/or more
efficient subsonic aircraft.
The sensor film will be ideal for measurement of pressure distribu
tions on moving and complex-shaped parts in both aerodynamic and
hydrodynamic experiments. Possible related applications include
shock wave sensors, radiation detectors, and image converters.
piezoelectric polymers, light-emitting diodes, pressure
distribution, polymer LED, pressure sensors, fast-response
Project Title:
Nonintrusive Flow Visualization to Locate Vortices and Laminar-to-Turbulent Transition
M.L. ENERGIA, Inc.
P.O. Box 1468
Princeton, NJ 08542-1468
93-103.06 7970 __ AMOUNT REQUESTED $ 70,000
Nonintrusive Flow Visualization to Locate Vortices and Laminar-to-Turbulent Transition
Abstract:
We propose to demonstrate a new optical measurement of velocity
gradient based on direct observation of the differential
displacement of a marked fluid element in ordinary, unseeded air.
The method utilizes a pulsed laser beam to "write" an arbitrary
pattern, such as a line or a cross, into air by means of stimulated
Raman vibrational excitation of oxygen. After suitable time delay,
during which the velocity gradient causes the pattern to distort,
the new pattern is determined via fluorescence induced by a second
laser beam. An image of the new pattern is captured with a video
camera. Distortion of a line will determine point of laminar-to-
turbulent transition, whereas rotation of a cross will yield
vorticity. By writing a grid, multiple spatial location can be
probed simultaneously. The use of a pair of cameras, imaging
orthogonal planes, results in a full, three-dimensional vector. The
accuracy of the method is limited only by the ability to determine
time and displacement, and can be performed at vector collection
rates of 30 Hz using commercially available equipment.
In this effort we propose a detailed study, including appropriate
laboratory proof-of-concept measurements, of the applicability of
the technique to advanced aircraft testing. The results of this
effort will be a prototype system designed for aircraft flight
testing applications.
The nonintrusive velocity gradient instrument would provide unique
new capability for a wide variety of fluid dynamics research and
development. Applications include fundamental studies of turbulence
and transition, CFD validation, and engine testing. Commercial
product development would create new enabling technology for
industrial, university, and government research and development.
Transition Determination; Aircraft Testing; Vorticity Measurement;
Flow Tagging; RELIEF; Nonintrusive Diagnostics
Project Title:
On-Line Monitoring of Engine Performance Parameters and Advanced
Scientific Monitoring, Inc.
1232 E. Broadway Road, Suite 210
Tempe, Arizona 85282
93-1 03.06 8362 __ AMOUNT REQUESTED $ 65,574.00
On-Line Monitoring of Engine Performance Parameters and Advanced
Algorithms to Identify Compressor Instabilities
Abstract:
Propulsion subsystems of future flight vehicles will run to higher
thermal and aerodynamic loads for increased efficiencies. Increased
loading and operating requirements cause serious mismatch between
stages and components during off-design conditions with attendant
compromise on stability margin.
Another factor that affects component efficiencies is deviation in
predicted performance due to in-flight damages and component aging.
This deviation can propagate into more serious problems if not
detected in time. More importantly, the deviation may be
misinterpreted by control and decision unit as problems in other
components. Misinterpretation of failures is crippling to future
engines and aircrafts that incorporate performance seeking control
methodology to optimize system performance on the fly.
To ensure reliable and sustained improvement in subsystem
performance, accurate monitoring and diagnosis are essential;
therefore, the firm proposes to conduct a program of research and
development on on-line monitoring of engine performance and
advanced algorithms to identify compression system instabilities.
This program will utilize artificial intelligence techniques and
analytical redundancy features. The diagnostic algorithms will be
model-based with inherent abilities to learn, reason, and adapt to
failures.
1) Enable practical implementation of active stall/surge control.
2) Enhance the operability and safety of gas turbine engines. 3)
Result in fault tolerant and adaptive systems. 4) Reduce costs in
hardware, fuel, operations, and logistics. 5) Approach true on-
condition maintenance goal. 6) apply to other physical systems as
aerospace traditionally leads in technology development.
health monitoring, diagnostic system, stall/surge, fault tolerance,
redundancy management, intelligent algorithm, turbine engine
Project Title:
Solution-Adaptive Computer Software for Preliminary Structural
ResearchSouth, Inc.
555 Sparkman Dr. Suite 818
Huntsville, Alabama 35816
93-1-03.07 1769 __ AMOUNT REQUESTED $ 70,000
Solution-Adaptive Computer Software for Preliminary Structural
Design of Hypersonic Vehicles
Abstract:
ResearchSouth, Inc. proposes to develop methodology and
preliminary
design computer software for the analysis of stiffened composite
panels used in designing hot structures on hypersonic vehicles.
Phase I of the development will investigate the following major
areas of the preliminary design of panel structures which are
subjected to severe thermomechanical loading during operation. We
will develop algorithms and strategies for determining critical
design condition loads from the output of finite element models
of
the structure. We will investigate at least three approaches: an
automated search program which will evaluate output files from
finite element models and define critical thermomechanical
loading
conditions and structural elements from time-consistent load
histories: a statistical model which uses the finite element data
from large samples and determines the most probable set of design
conditions: and a deterministic mathematical model in which a
functional is formed using the finite element data base with the
design condition combinations being produced by a calculus of
variations minimization solution. We will also develop a buckling
analysis program which uses conventional analytical methods to
define the buckling loads and margins of safety of critical
equivalent stiffened panels. We will investigate, demonstrate and
deliver adaptive meshing software to improve the resolution of
internal loads and the capture of peak moments in stiffened
panels
and substructure for evaluation of local crippling of the hot
structure. Prototype software will be available and delivered at
the end of the Phase I effort. Phase II will extend the concepts
and software to the operational mode, interfacing with most
commercially-available finite element structural packages.
Benefits
to NASA will include more cost-effective preliminary design
programs and more reliable designs.
The structural design software will be used by aerospace,
mechanical, and civil engineers on all disciplines which require
a
conceptual and preliminary design phase. Airplane companies,
automobile manufacturing facilities, watercraft designers,
building
and facility engineers, and bridge construction companies are
among
the potential users for this product.
Preliminary Design, Finite Element Methods, Solution-Adaptive
Methods
Project Title:
Oblique Detonation Wave Hy-Scram Engine for Hypersonic Propulsion Applications
Advanced Projects Research Incorporated
5301 N. Commerce Ave., Suite A
Moorpark, CA 93021
93-103.07 2585 __ AMOUNT REQUESTED $ 70,000
Oblique Detonation Wave Hy-Scram Engine for Hypersonic Propulsion Applications
Abstract:
The Oblique Detonation Wave Hypervelocity Scramjet (ODW Hy-Scram)
Engine is applicable to hypersonic flight vehicles that require
high Mach Scramjet operation. This project will implement a unique
new analysis capability to analyze and assess a novel propulsion
device that could greatly enhance applications in the hypersonic
class of flight vehicles. The ODW Hy-Scram Engine is configured to
use gas dynamic wave interactions to provide inlet stream primary
compression (after vehicle forebody compression), bulk ignition,
and rapid combustion. The major advantages over previous Scramjet
engines are: 1) use of the vehicle forebody for fuel injection and
complete mixing (due to longer distances, lower temperatures and
lower pressures than is typical in the inlet fuel injection systems
of Scramjet Engines), 2) simpler and shorter inlet design due to
lower Mach range through which the flow must be decelerated
(typically incorporated into the vehicle forebody), and 3) shorter
and simpler combustor design. The primary benefit of this approach
is the reduction of the weight associated with the propulsion
system for a given combustion efficiency. The secondary benefit is
stabilized combustion due to the bulk ignition of the fuel and
oxidizer in the stable over driving of the oblique detonation wave.
The ODW Hy-Scram is applicable to future hypervelocity flight
vehicles which require velocities above Mach 8. Specifically, NASP,
Trans-Atmospheric Vehicles (TAV's) and hypersonic cruisers such as
reconnaissance aircraft. Most beneficial, however, would be a test
platform from which to conduct hypersonic flight tests.
Scramjet, Oblique, Detonation, Hypersonic, Propulsion
Project Title:
HEAT EXCHANGER/REACTOR FOR ENDOTHERMIC FUELS IN HYPERSONIC
Creare Incorporated
P.O. Box 71
Hanover, NH 03755
93-103.07 3800 __ AMOUNT REQUESTED $ 69,950
HEAT EXCHANGER/REACTOR FOR ENDOTHERMIC FUELS IN HYPERSONIC
PROPULSION SYSTEMS
Abstract:
Aircraft which travel at high Mach numbers require a very large
internal heat sink to protect the engine and airframe from high
heat loads. Endothermic fuels are attractive for hypersonic
propulsion systems because they increase the fuel heat sink
capacity. We propose to develop a compact and lightweight heat
exchanger/reactor in which cooling is provided by the catalyzed
decomposition of the endothermic fuel. The innovation is a heat
exchanger configuration which enables efficient decomposition of
the fuel within a very small volume, resulting in an order of
magnitude reduction in the size and a factor of three reduction in
weight of the reactor. There are three key advantages to the
proposed heat exchanger: small size and weight, increased
reliability due to a simplified internal configuration, and low
pressure drops for air cooling applications. Preheating of the fuel
occurs within the same compact unit. The objectives of Phase I are
to prove the feasibility by demonstrating fabrication and sealing
techniques and to assess the benefits to hypersonic propulsion
systems. In Phase II we will build and demonstrate a prototypical
reactor/heat exchanger and perform tests to provide data for design
and optimization of hypersonic propulsion systems.
The proposed reactor/heat exchanger enables flight at high Mach
numbers by providing cooling for high thermal loads in a small,
flight-weight unit. These reactor/heat exchangers can ultimately be
sold to NASA, the Air Force, or commercial aircraft integrators.
The heat exchanger can also operate as a compact gas-to-gas
recuperator with low pressure drops for aerospace applications,
cryogenics, and power generation.
thermal management, hypersonic aircraft, endothermic fuels
Project Title:
Hypersonic Neurocontrol Actuator and Testbed
Accurate Automation Corporation
7001 Shallowford Road
Chattanooga, TN 37421
93-1 03.07 4646 Amount Requested $70,000
Hypersonic Neurocontrol Actuator and Testbed
Abstract:
The purpose of this proposal is to develop a new generation of
"SMART" neurocontrol actuator system for use on Hypersonic
aircraft. Develop a testbed to validate that the actuator system
will work. This will also optimize and scale the testbed vehicle
sizing. This concept using adaptive neural network technology will
improve performance and behavior for Hypersonic aircraft like the
National AeroSpace Plane.
Develop a new generation of actuator and control system for
aircraft.
Hypersonic, NASP, Neural Network, Neurocontrol, Actuator
Project Title:
AUTOMATED ENGINE CONTROL and FACULTATIVE FUEL INJECTION SYSTEM
LOWI ASSOCIATES WEST, INC.
2146 Toscanini Drive
Rancho Palos Verdes, CA 90732
93-103.08 8457 __ AMOUNT REQUESTED $ 70,000
AUTOMATED ENGINE CONTROL and FACULTATIVE FUEL INJECTION SYSTEM
Abstract:
An analytical investigation is proposed that aims to establish
technical support for an automated engine control and facultative
fuel injection system suitable for a candidate prop-drive power
plant capable of providing propulsion for a very high altitude
unmanned aircraft. The proposed system would provide full-authority
digital control of the principal engine operating variables such as
shaft speed, torque, injection timing and the like as well as
starting sequences and parameter optimizations connected with
operation on alternative fuels and available air. By these means,
a facultative engine can be implemented whereby a highly variable
amount of air can be efficiently utilized to conserve expendables
to the benefit of payload, range, and endurance. The proposed
system would be electrohydraulically operated and regeneratively
cooled with circulated fuel thereby eliminating external cooling
provisions and cumbersome mechanical drives and controls while
providing convenient packaging and automation interfaces for remote
command and control.
The proposed investigation will examine the transient hydraulic
effects, injection pulse profiles, turn-down range and design
details of the components required to implement a common rail,
solenoid-controlled electrohydraulic unit injection system subject
to microprocessor control. Control algorithms, sensors and external
signal interfaces will also be defined.
An improved, full-authority electronic fuel injection system for
diesel engines has numerous applications in emission-controlled
vehicles and in automated industrial and aircraft engine power
situations. Other possible uses include multi-fuel and flexible-
fuel engine applications where free oxygen is either not available
for combustion or is deficient for the power output required.
Digital controlled, Electrohydraullically operated, Closed-loop
Fuel Injection
Project Title:
Thrustmeters For Engine Management And Control Systems
TMI
P.O. Box 11289
Fort Wayne, IN 46857-1289
93-103.09 0586 __ AMOUNT REQUESTED$ 70,000.00
Thrustmeters For Engine Management And Control Systems
Abstract:
A simplified display which shows real-time thrust reduces pilot
workload and increases safety in jet aircraft. Engine thrust, one
of the more important engine parameters, is not currently measured,
but is estimated from various sensor readings, such as EPR (Engine
Pressure Ratio), spool speed, fuel flow, and turbine inlet
temperatures. This project will demonstrate the advantages of using
a system that computes net thrust by measuring gas flow in the
engine exhaust and exhaust sections to calculate net thrust. The
thrust will be presented on a unique color pictorial display, the
Engine Control and Management System (E-MACS) developed by NASA.
Real-time thrust gives the pilot an instant snapshot of engine
health, improving reaction time during critical flight regimes such
as take-off and landing. These measurements provide valuable
information for adjusting each engine to optimize performance and
efficiency.
The E-MACS system has been well received by pilots and will be
enhanced by the addition of real-time thrust measurements.
Potential customers include all forms of commercial aviation and
military aircraft.
Thrust Measurement, Cockpit Displays, Engine Management, Ergonomics
Project Title:
NOVEL ANGULAR POSITION SENSOR
Aztec Systems
45 Aldrich Road
Watertown MA 02172
93-103.09 9890 __ AMOUNT REQUESTED $70,000
NOVEL ANGULAR POSITION SENSOR
Abstract:
We propose to develop an innovative, light and non-cumbersome
angular position sensor for hands, arms or a helmet for use in
virtual reality systems and enhanced space-crew interfaces.
This research will develop reliable, unobtrusive and inexpensive
angular position sensors for virtual reality and robotic machinery
control. Such sensors can also be utilized in novel computer user
interfaces.
Angular Sensor Encoder
Project Title:
Polynomial Networks for Testing Flight Critical Systems
AbTech Corporation
508 Dale Avenue
Charlottesville, VA 22903
93-1 03.10 0686 Amount Requested $69,766.64
Polynomial Networks for Testing Flight Critical Systems
Abstract:
The objective of this effort is to demonstrate a prototype model of
a flight-critical system using AbTech's AIM network synthesis tool
and NASA's CLIPS production rule system and to demonstrate the
ability of an AIM generated polynomial network to reliably perform
sensitivity analysis using variable components of this flight
critical system. The resulting adaptive test generation, analysis,
and control modeling system will demonstrate the feasibility of
developing a revolutionary test definition and analysis product
capable of adapting in a dynamic environment, monitoring and
diagnosing complex system behavior, and predicting future faults
and maintenance requirements. The innovation is the application of
learning software to modeling, sensitivity analysis, and test-
synthesis and diagnosis. The AIM test system is designed to
enhance a systems engineer's ability to understand system
interactions, make decisions on a systems ability to complete a
desired function, determine the effect that a component has on the
overall system, and perform system validation. In Phase I we will
demonstrate the ability of AIM to model a flight critical system,
perform sensitivity analysis, and to test for validating
functionality and operability.
This system could be adapted to be used on many large systems to
assist with test plan development and analysis of results.
Automated modelling of processes from functional descriptions
provides an efficient means of producing system simulators for
various applications.
Test Generation, Analysis, Sensitivity Analysis, Polynomial
Networks, AIM
Project Title:
Integrated Systems Validation Environment Platform for Flight-Critical Systems.
Systems Control Technology, Inc.
2300 Geng Road
Palo Alto, California 94303
93-103.10 2233 __ AMOUNT REQUESTED $ $69,989
Integrated Systems Validation Environment Platform for Flight-Critical Systems.
Abstract:
The innovation proposed by this SBIR will research and implement an
integrated systems environment that addresses the technology needs
of verification and validation and systems health monitoring of
flight critical systems (FCS). This research will define and
implement a common environment platform that provides seamless
integration of current and future FCS analysis and test tools. The
primary thrust of this research will be in the validation phase,
supporting test preparation, real-time simulation, and real-time
health and system status monitoring in flight test. This integrated
systems validation environment platform will shorten the time to
verify flight critical systems and will provide added safety during
flight test. This effort will develop an environment that will
integrate a number of current analysis tools and provide new
capabilities for monitoring, analyzing, and evaluating real-time
FCS data from on-board systems and real-time simulations of such
systems. The Phase I effort will provide a requirement's definition
prototype demonstration and a verified design for an innovative FCS
validation and test monitoring work station environment. The Phase
II effort will implement the environment and selected tools to
provide an environment platform that will yield a quantum
improvement in the effectiveness and efficiency.
The proposed project will result in a technology for integration of
diverse engineering analysis tools. Such a technology would have a
multitude of applications in industry and in research. The Phase II
effort will provide an analysis and test environment that is of
immediate use to other potential customers including, Air Force:
ASC SPOs, WL, ESD, and Weapons Development; Army; Navy; aircraft
primes; electronic system developers; and College/University
systems.
Verification & Validation; Safety of Flight; Open-System
Architecture; Flight-Critical Systems; Systems Health Monitoring;
Automated Testing
Project Title:
A Finite Element CFD Analysis for Turbulent and Chemically Reactive Flows Around Aerospace Vehicles
Engineering Computations
18814 Rochelle Avenue
CERRITOS, CA 90701
93-103.11 1669 __ AMOUNT REQUESTED $ 70,000.00
A Finite Element CFD Analysis for Turbulent and Chemically Reactive Flows Around Aerospace Vehicles
Abstract:
This proposal is concerned with the development of a finite rate
turbulent combustion algorithm and associated software to simulate
the chemistry that occurs in realistic turbulent mixing/reacting
flows. A two-tiered approach will be adopted for turbulence
modeling, namely a Reynold averaged Navier-Stokes solutions with
turbulence modeling, and more importantly a direct numerical
simulation that does not require turbulence modeling.
A finite element approach will be adopted for modeling and
simulation of turbulence and combustion in fluid flow. Phase I
effort will demonstrate the feasibility of the proposed techniques
for 2-D flow problems. A pilot code incorporating this capability
will be generated and integrated with NASA STARS multidisciplinary
program. The proposed innovation will provide a more efficient and
accurate integrated design of aerodynamics, structures, and control
systems for modeling and simulation of advanced aerospace vehicles
such as the hypersonic NASP. The pilot code will also be installed
on a parallel processing system such as the IBM RS/6000 Model 590
(8 cpu's) machine to demonstrate that, by adopting an optimum
combination of efficient software and dedicated low cost
commercially available computers, complex practical problems can be
solved within.
The 2-D approach to be developed in Phase I plan will be extended
to the more general 3-D case under Phase II. Associated code will
be fully integrated with NASA STARS multidisciplinary finite
element program. The integrated capability will be extremely useful
for accurate modeling and simulation of advanced aerospace
vehicles.
Turbulence; Combustion; Finite element method; Multidisciplinary
simulation, Aerospace vehicle simulation
Project Title:
New High AOA Departure Criteria for High Agility Fighters
Eidetics International, Inc.
3415 Lomita Blvd.
Torrance, CA 90505
93-1 03.11 8228 Amount Requested $69,992
New High AOA Departure Criteria for High Agility Fighters
Abstract:
Fighter agility is comprised of both maneuverability and
controllability. Inadequate controllability can limit the agility
potential through a combination of reduced control power and/or a
lack of bare airframe departure resistance. Typical departure
criteria include only static aerodynamic terms and are not adequate
predictors for modern fighter aircraft performing high-agility
maneuvers such as loaded roll motions. The development of a
reliable departure resistance design criteria for highly agile,
highly augmented fighter aircraft and the exploration of validation
methods using 6-DOF computations and comparisons to existing flight
data from the F/A-18 HARV is the subject of this study
The innovation in Phase I is the inclusion of appropriate dynamic
aerodynamic terms and the effects of flight control system inputs
to evaluate the departure characteristics of a highly augmented
high agility aircraft. Phase I will develop the enhanced criteria
and demonstrate methodologies for validation. Phase II will
accomplish the validation with flight test data from NASA
Ames/Dryden for the F/A-18 HARV, x-31 and X-29A aircraft. The
expected payoff will be a validated tool to evaluate agility and
departure tradeoffs in preliminary design that will result in
significant cost and time savings in the development of new
configurations and will provide an additional means of evaluating
the performance characteristics of augmented aircraft prior to
flight.
Benefits from a validated advanced agility/departure criteria
including dynamic terms and flight control system inputs are
availability of a proven systematic evaluation of agility and
departure resistance of new configurations early in their
development so critical decisions can be made concerning
configuration definition and related flight control system
requirements. Benefits of early definition are reflected in
substantial savings in time and development costs. Validated
criteria also allows government procuring agencies to better
evaluate the agility potential of new aircraft designs prior to
flight tests by using aerodynamic data from ground tests or
computational means more effectively.
Fighter, Agility, Controllability, Departure Criteria, High Angle
of Attack
Project Title:
Evaluation of Indicial-Function Approach Using an Euler Finite-Element CFD Code
McIntosh Structural Dynamics, Inc.
883 N. Shoreline Blvd., Suite B200
Mountain View, CA 94043
93-103.11 9277 __ AMOUNT REQUESTED $ 52,443.
Evaluation of Indicial-Function Approach Using an Euler Finite-Element CFD Code
Abstract:
New methods are proposed for achieving fast execution of
aeroservoelastic aerospace vehicle flight-characteristics
simulations. Specifically, the exploitation of approximate
solutions that appear in the indicial-function representation of
generalized aerodynamic forces is proposed. The essence of the
innovation is transformation of the convolution integrals into a
set of linear first-order differential equations that augment the
system state vector; these added states are to be solved
concurrently with the other system states that describe the rigid
and elastic motions of the vehicle. The principal Phase I
objectives are to demonstrate this indicial-function procedure with
a finite-element Euler code and to document the reduced overall
effort required for simulation studies in comparison with direct
coupling of the Euler code with the solution of the vehicle motion
equations.
Potential commercial applications include incorporating the new
approach into existing NASA software and porting the code to
parallel-processing environments
Indicial functions, aeroservoelasticity, simulation
Project Title:
Noise Cancelling Fiber Optic Microphone
Micro-Optics Technologies, Inc.
8608 University Green #5
P.O. Box 620377
Middleton, WI 53562
93-103.12 0655 __ AMOUNT REQUESTED$ 67,958
Noise Cancelling Fiber Optic Microphone
Abstract:
Intelligible Voice communication in aviation systems is critical
for efficient and safe performance. This work will develop a noise
cancelling fiber optic microphone that can be used in electrically
and acoustic noisy environments. Two pressure fiber optic
microphones (FOM), a lens FOM and a shutter FOM, will have their
acoustic cavities designed so that they are noise cancelling. The
difference in phase and arrival time between sounds generated close
to the microphone and those generated farther away will be
exploited to achieve the noise cancelling performance.
Both microphones are extrinsic, intensity modulated fiber optic
pressure microphones using multimode fibers. By designing the
acoustic cavity of the t