NASA 1990 SBIR Phase 1 Solicitation

Project Title:

Advanced Turbomachinery CFD design and Analysis Program

01.01-1515
900394
Advanced Turbomachinery CFD design and Analysis Program

Abstract:

Computational fluid dynamics (CFD) tools have now developed to the point where they
can be reliably used for the design, evaluation, and analysis of high-performance
gas turbines, such as those used in modern aeronautical propulsion systems. For these
applications, it is necessary to use a three-dimensional viscous CFD code that combines
efficiency, accuracy, and user-friendliness. For axial turbomachinery, prediction
and analysis of secondary flows, blade heat transfer, transition, and unsteadiness,
at on- and off-design conditions, require the use of new, advanced models like that
provided by renormalization group (RNG) methods developed by the company. This project
will develop enhanced supercomputer and massively parallel processor versions of
the NEKTON CFD code with RNG models for transition and turbulance to address turbomachinery
applications. This involves integrating variable geometry, complex blade rows, transition
and turbulence modelling, and shock-boundary layer interactions while addressing
central compressor, diffuser, and turbine design issues.
This program should find wide application in the advanced design of gas turbine devices
and stream turbomachinery with wide industrial applications.
turbomachine, computational fluid dynamics, renormalization group

Project Title:

A Probability Density Function (PDF) Method for Turbulent Reacting Flows

01.01-6576
900683
A Probability Density Function (PDF) Method for Turbulent Reacting Flows

Abstract:

Modeling methods developed for non-reacting turbulent flows are not able to capture
important turbulence/combustion interactions. An alternative approach solves an equation
for the joint probability density function (pdf) of the local velocity and composition,
instead of solving a set of equations for their first- and second-order moments.
While pdf methods have been proposed in the past, they have only been used in certain
simplified situations. In this project, the company will develop an efficient pdf
solution procedure for general reacting flows. In Phase I, a stand-alone module will
be developed using a Lagrangian Monte Carlo solution method. The module will be validated
by comparison with benchmark data. These comparisons will be used to assess the feasibility
of the pdf method and to determine the requirements for coupling the module with
a finite-volume CFD code. In Phase II, the coupling would be performed and the methodology
extended to three-dimensional flows. The pdf module and finite volume code will be
fully documented and delivered to NASA at the end of Phase II.
The developed pdf module and coupled CFD code will advance the state-of-the-art of
numerical simulations of turbulent reactive flows, and will be of significant interest
to all organizations associated with aeronautical and space propulsion systems.
turbulent reacting flows, turbulence-combustion interactions, monte corlo methods,
probability density functions, computational fluid dynamics

Project Title:

A New Unsteady Mixing Model to Predict NOx Production During Rapid Mixing in a Dual

01.01-9500
900831
A New Unsteady Mixing Model to Predict NOx Production During Rapid Mixing in a Dual

Abstract:

Stage Combustor
An advanced gas turbine engine to power supersonic transport aircraft is currently
under study. In addition to high combustion efficiency requirements, environmental
concerns have placed stringent restrictions on the pollutant emissions from these
engines. A combustor design with the potential for minimizing pollutants such as
NOx emissions is undergoing experimental evaluation. A major technical issue in the
design of this combustor is how to rapidly mix the hot fuel-rich primary zone product
with the secondary diluent air to obtain a fuel-lean mixture for combustion in the
secondary stage. Numerical predictions using steady-state methods cannot account
for the unsteady phenomena in the mixing region. Therefore, this project is addressing
a novel unsteady mixing model that can be used to evaluate mixing and combustion,
including NO production within the mixing region,  This model will be developed to
be used in conjunction with steady-state prediction methods and thus will have the
potential for providing an improved engineering design analysis tool. The capability
of this model will be demonstrated in Phase I with the eventual objective of coupling
the model to a steady-state solver in Phase II.
The model of unsteady mixing in realistic gas turbine combustors can be utilized
for a variety of design and analysis work both by the government and by the engine
manufacturing industry.
NOx production, rapid mixing, linear eddy, combustion, turbulent mixing, finite-rate
kinetics, entrainment, molecular diffusion

Project Title:

Compact Gas Turbine Engine with Effective Turbine

01.02-0875
901215
Compact Gas Turbine Engine with Effective Turbine

Abstract:

This project is investigating an innovative compact configuration of the gas turbine
engine that has unusually effective cooling of turbine blades. This could result
in higher turbine inlet temperatures, power, and efficiency than is common in turbines.
Because of its inherent low pressure ratio, the engine would be suited to, but not
limited to small scale applications. Phase I will study the effectiveness of blade
cooling and the potential benefits of elevated allowable turbine inlet temperatures
and explore the necessity for regeneration in a low-pressure-ratio, gas turbine engine.
If power and efficiency are enhanced as preliminary estimates would indicate, the
engine could compete for many applications now employing much more bulky piston engines.
It would be particularly attractive where a high degree of portability is important
as in emergency power or pumping stations, and vehicle propulsion.
Possible applications include efficient, high-output emergency power sources for
electricity, vehicles propulsion, or pumps for fire fighting or flood drainage.
turbine blade cooling, compact gas turbine engine, regeneration, low pressure ratio,
high turbine temperature, high power to weight ratio

Project Title:

Enhanced Diagnostic Methods for Planetary Gear Systems

01.02-3779
900618
Enhanced Diagnostic Methods for Planetary Gear Systems

Abstract:

Diagnostic fault detection requires knowledge of failure modes, recognition of measurable
fault patterns, and implementation of optimized signal processing. Many of today's
rotorcraft transmissions use planetary-gear reduction systems; these systems pose
a complex problem in the diagnostics field due to the non-fixed axis gears and bearings
present therein. This project will explore methods to increase the fault signal-to-noise
ratio for planetary systems though an integrated approach using the hunting tooth
period, innovative sensors and sensor locations, structural transmission path analysis,
and high frequency data processing techniques. The approach involves developing computer
based models for planetary gear system performance and fault patterns. In conjunction
with the computer models, diagnostic process algorithms will be built to optimize
detection of the predicted fault patterns. The algorithms will be tested on data
obtained with a gearbox monitoring system. Additionally, hardware requirements for
planetary-gear system monitoring will be developed. The resulting advances in planetary
gear diagnostics will be integrated with an on-going gear-monitoring research to
develop a unified approach to helicopter gear box monitoring.
This technology would augment diagnostic systems currently available.
planetary gear systems, hunting tooth vibration, diagnostics, testing

Project Title:

Novel Catalytic Approach to Combustion

01.02-5215
900774
Novel Catalytic Approach to Combustion

Abstract:

This project is developing a novel catalytically ignited, plug-flow combustor which
will improve gas turbine performance. Based upon prior SBIR projects and internal
research, the project will experimentally test key aspects of this improved catalytic
combustor, demonstrating improved operational limits. This new approach to the catalytic
combustor offers the potential for plug flow combustion at high velocity and temperatures
along with exceptional multifuel, turndown, and high-altitude, re-light capabilities.
Commercial applications include combustors for all types of gas turbine engines.
Data developed will also be helpful for other applications of catalytic ignition
and combustion.
catalytic, gas turbine, combustion

Project Title:

Integration of Combustor Aerodynamics and Fuel Spray to Increase Turndown Fuel-Air

01.02-6576
900445
Integration of Combustor Aerodynamics and Fuel Spray to Increase Turndown Fuel-Air

Abstract:

Ratio in Small Gas Turbine Combustors
This project will integrate combustor aerodynamics and fuel spray patterns to attain
high turndown ratios without significantly modifying conventional combustor geometry.
This will be accomplished by: the creation of two distinct zones within the combustor
primary zone which are independently fueled; use of a dual-lip airblast fuel atomizer
which fuels only the central recirculation zone at low power conditions and both
the dome and central recirculation zones at full power; and employment of staggered,
widely-spaced, upstream-angled primary holes that allow jet penetration into the
dome zone. In Phase I, three-dimensional CFD analysis will be performed on the advanced
configuration as well as a conventional configuration. Comparison will be made to
show the advanced design's potential of increasing turndown fuel-air ratio without
producing excessive smoke emissions. In Phase II, the design would be further optimized.
A sector combustor will be designed, fabricated and tested at various power settings
to experimentally demonstrate the concept.
The final products of this project would be of interest to manufacturers of gas turbine
engines and to government agencies responsible for combustor evaluation.
combustors, primary zone, swirlers, fuel injectors, gas turbine engines

Project Title:

New Distributed Fiber-Optic Sensors Based on Counter-Propagating Waves

01.03-1228
901854
New Distributed Fiber-Optic Sensors Based on Counter-Propagating Waves

Abstract:

A novel fiber optic approach is taken in this project to the distributed sensing
of forces and temperatures simultaneously at different locations with a single long
optical fiber probe. This concept uses temperature- and/or force-dependent stimulated
light amplification processes at each sensing point along the fiber probe. The approach
is designed to generate, at each sensing point along the fiber, optical signals unaffected
or only minimally affected by the magnitude of the forces and/or temperatures at
other points along the fiber. In contrast to presently known methods, our approach
does not require measurements of the state of polarization of the light at any point
along the fiber probe, and it should be implementable with relatively simple instrumentation.
The system should find applications in the monitoring of the structural integrity
of buildings, bridges, pipelines, and aircraft structures, and for implementing effective
process control in a wide variety of industrial processes.
fiber optics, sensors, distributed, raman amplification

Project Title:

Remote, Wireless Monitoring of Positron Escape for Gauging Temperature and Strain

01.03-6000
900505
Remote, Wireless Monitoring of Positron Escape for Gauging Temperature and Strain

Abstract:

This project will investigate monitoring of strains and temperatures based on the
unique electrical properties of positrons at metal surfaces. Unlike bound electrons,
positrons are often actively expelled from metals due to a net negative work function
which can be sensitive to strain or temperature. Sources can be inexpensively created
inside a metal component by accelerator activation. The fraction of positrons leaving
the surface would be affected by a number of strain or temperature sensitive variables,
such as work function, defect density, grain-boundary size, and conductivity. Thus,
monitoring of annihilation gamma rays away from the activated surface will indicate
strain or temperature as in conventional sensors but at much higher temperature and
with none of the disadvantages which characterize electrical or optical fiber connections.
This would be ideal for operating high-temperature engines, particularly on rotating
parts. Refractory materials could be used at extremely high temperatures, over 2000oC.
Rapidity of measurement would be a function of source strength, but quite modest
sources which do not involve any hazard or special handling could produce reliable
measurements every 10 to 20 seconds.
Wireless, high-temperature gauges would have widespread application in advanced engine
testing and development.
strain, thermometry, radiometry, sensors, gauges, positron, transducer, wireless.
strain, thermometry, radiometry, sensors, gauges, positron, transducer, wireless

Project Title:

Laser-Driven Hypersonic Airbreathing Propulsion Simulator

01.04-0003
901053
Laser-Driven Hypersonic Airbreathing Propulsion Simulator

Abstract:

This project addresses a novel concept for incorporating propulsive effects into
wind tunnel testing of hypersonic aircraft models. The concept involves using a laser
beam to add heat to the airflow entering the aircraft's power plant which is a ramjet
engine. The beam, which may be from a continuous wave or a repetitively-pulsed laser,
enters the nozzle and is focused at a spot. Heat transfer occurs due to absorption
of energy at laser wavelengths into the gas. It is envisioned that a commercially
available CO2 or other similar lasers will be suitable for current applications.
It appears plausible to produce thrust of one engine for a 1/100th scale model of
a typical multi-engine hypersonic vehicle without requiring prohibitive laser power
levels. If the concept is shown to be feasible, and can be demonstrated experimentally,
a significant new dimension will be added to the utility of high speed wind tunnels.
A simultaneous experimental simulation of aerodynamic and propulsion (or propulsion-induced)
effects will become possible.
The simultaneous experimental simulation of aerodynamics and propulsion, particularly,
the effects on aircraft drag, will add a new dimension to wind tunnel test methodology.
laser propulsion, propulsion simulation, propulsion-induced aerodynamics, hypersonic
testing

Project Title:

Solution Adaptive Gridding within the Chimera Grid Scheme

02.01-2027
901921
Solution Adaptive Gridding within the Chimera Grid Scheme

Abstract:

This project is concerned with the development of a computational tool that combine-solution-adaptive
techniques with an overset grid technique to solve unsteady aerodynamic problem in
such areas as powered lift, helicopter wake resolution, and high alpha, enhanced
maneuverability aircraft. Both techniques have been used to attempt to simplify the
task of generating efficient meshes for computational simulations, but grid generation
remains an obstacle to quick, accurate flow field simulations. The coupling of these
two techniques would allow for faster, more accurate grid generation, as well as
general purpose grids that would be well-suited for a range of flow field conditions.
This would greatly reduce the need to compute new grid systems for each new set of
flight conditions. In addition, a particular aspect of the Chimera scheme that can
allow relative motion between grids can be utilized by the solution adaptive technique
to compute time dependent adaptations.
Military and commercial aircraft designs for such aircraft as high maneuverability
fighters, powered lift vehicles, and helicopters would be improved with the advanced
simulation capabilities developed in this effort.
unsteady aerodynamics, solution adaptive grids, overset grids

Project Title:

A New Subgrid Model for Large-Eddy Simulations of Mixing and Chemical Reaction in

02.01-9500
900757
A New Subgrid Model for Large-Eddy Simulations of Mixing and Chemical Reaction in

Abstract:

Turbulent Flows
Conventional, turbulent-mixing models based on gradient-diffusion assumptions are
not capable of accurately predicting mixing and reaction rates in most practical
combustion devices. Furthermore, at the small scales, most conventional models make
no distinction between turbulent conversion and molecular diffusion. This distinction
is critical for the accurate description of the mixing process. In addition, it is
known that turbulent mixing and entrainment processes in shear flows are dominated
by unsteady, large-scale, vortical motions. The spatial and temporal evolution of
these large-scale structures cannot be modeled and must be explicitly computed for
accurate predictions. Phase I will explore subgrid modeling techniques for use in
large-eddy simulation (LES) of reacting flows. In particular, a model for mixing
and chemical reactions at the subgrid level, in both low- and high-speed flows, will
be developed based on Kerstein's linear-eddy approach. LES of incompressible, two-dimensional
mixing layers will be performed and the results will be compared with high-resolution
direct numerical simulations and available experimental data to assess the proposed
subgrid model. In Phase II, this model would be extended to study three-dimensional,
compressible reacting flows with heat release.
A predictive capability for unsteady simulation of combustion in both low- and high-speed
flows with full coupling between the chemical heat release and the fluid dynamic
flow field can be utilized for a variety of purposes by both government and industry.
turbulent mixing, large-eddy simulation, chemical reactions, subgrid modeling, supersonic
flows, multispecies mixing, linear eddy, compressible flows

Project Title:

Nonlinear Control of Shear Flows

02.02-9457B
901614
Nonlinear Control of Shear Flows

Abstract:

Chaos theory has recently suggested two innovative strategies for active control
of general, nonlinear systems. Both are potentially applicable to the problem of
controlling shear flows, whether it be to enhance or suppress the effects of turbulence.
Each makes essential use of the nonlinear character of the system to obtain control.
In model studies of nonlinear oscillators, control by one of these methods has already
produced dramatically better results then traditional linear methods. The question
whether these control schemes be made to work in bounded and unbounded shear layers
will be addressed by this project. Work will be done to determine the feasibility
of their application, to judge the suitability of each method in closed and open
flows, to suggest guidelines for their implementation, and to test them both on a
model problem that can display the mathematical character of either full development
and testing of nonlinear flow control schemes capable of substantial skin-friction
and heat-transfer reductions at walls and mixing enhancement in shear layers and
jets.
A practical flow control system that could decrease drag, heat transfer, and structural
vibration, increase payloads and propulsive efficiency, and enhance maneuverability
could have substantial impact on the economics of commercial flight operations.
nonlinear flow control, chaos, turbulence, shear flows

Project Title:

Hypervelocity Launcher for Aerothermodynamic Experiments

02.03-1806
901232
Hypervelocity Launcher for Aerothermodynamic Experiments

Abstract:

The development of hypersonic aerospace vehicles requires detailed knowledge of the
aerothermodynamic (ATD) environment in which the vehicle will be operated. Experimental
study of ATD parameters at greater than 6km/s is presently not feasible. The goal
of this project is to develop the technology base and demonstrate an electromagnetic
gun system capable of achieving greater than 6km/s launch velocity. The object is
to develop a distributed, energy-storage concept for powering railguns to push the
system energy conversion efficiency to more than 80 percent. This high efficiency
at hypervelocity will make ATD testing at greater than 6km/s feasible.
There are several potential applications of launchers capable of reaching >10km/s.
These include impact fusion, equation-of-state testing, and earth-to-space launch.
hypervelocity, railgun, aerothermodynamic, experimental

Project Title:

Innovative Model for Reacting Flows

02.03-3013
901389
Innovative Model for Reacting Flows

Abstract:

This project explores the benefits of a new computational model for reacting flows
which applies to nonequilibrium flows, in general, but is specially designed to address
the frequent condition in hypersonic flows where some of the reactants are near thermochemical
equilibrium, while the remainder are out of local equilibrium. Nonequilibrium flows
are present in several vehicles of interest to NASA, including future Space Shuttles,
the National Aerospace Plane, hypersonic transportation, aerobraking orbital transfer
vehicles, and planetary probes. Numerical methods to compute nonequilibrium flows
involving a moderate to large number of reactants are costly to operate and can benefit
substantially from simplifications; in some cases such simplifications are key to
the practical feasibility of the computations. The model based on past experience
with magneto-hydro-dynamic channel flows, and testing it numerically under hypersonic
flight conditions to assess its potential pay off for further Phase II development
and validation.
If the proposed model proves to be robust and to generate substantial cost savings,
commercial development for application to a variety of problems will be feasible.
hypersonic flow, nonequilibrium

Project Title:

Hypersonic Analysis for Vehicles in the Continuum-Transition Regime

02.04-3304
901483
Hypersonic Analysis for Vehicles in the Continuum-Transition Regime

Abstract:

Several aerospace vehicles are currently being considered that have a significant
portion of their flight path in the upper reaches of the atmosphere. The flow about
these vehicles is in the continuum-transition regime where the standard equations
of continuum flow, the Navier-Stokes equations, begin to fail. We propose to modify
the HANA code, an existing Navier-Stokes code for the analysis of hypersonic vehicles
to solve the Burnett equations with coupled, rotational nonequilibrium. The Burnett
equations are more accurate than the Navier-Stokes equations for low-density flows
with finite thickness shocks. Solutions to the Burnett equations have only recently
been obtained for the hypersonic flows. The Phase I investigation will determine
the viability of solving the Burnett equations with coupled, rotational, nonequilibrium
and surface-slip, boundary conditions within the HANA code. In particular, the ramifications
of using upwind differencing of the inviscit fluxes and diagonalized viscous Jacobians
in the LU-SGS implicit method will be studied. The proper implementation of surface-slip,
boundary conditions will also be considered.
The proposed Burnett equation code will benefit existing and future hypersonic vehicle
development programs both within government and industry. The code will be marketable
to the aerospace industry.
hypersonic, CFD, Burnett, rarified, continuum-transition, implicit, upwind

Project Title:

Rarefied Gas Effects on Aerobraking/Reentry Vehicles with Wakes

02.04-8581
900293
Rarefied Gas Effects on Aerobraking/Reentry Vehicles with Wakes

Abstract:

Aerobraking vehicles (AOTV, ASTV and vehicles to Mars) are going to make several
passes and dip low in the transitional regime in order to achieve the desired reduction
in velocity. Even at the lowest point of the trajectory, surface-slip effects persist
and real-gas effects due to nonequilibrium dissociation and ionization significantly
alter the flow structure. Further, due to impingement of the shear layer on the vehicle
payload, it has become imperative to investigate accurately the complete flowfield
with wake closure on the vehicle in the presence of slip and real-gas effects. This
project will investigate the hypersonic-rarefied flow phenomena on a complete body
including wake with slip and real-gas effects from the upper rarefied region to the
lower continuum region of the transitional regime by incorporating in the mathematical
analysis of the Navier-Stokes equations with slip, an adaptive grid-generation technique
which will accurately resolve the shock structure zone, and the highly viscous region
near the surface. In Phase I, a suitable, adaptive-grid generation technique will
be incorporated in the mathematical model of the stagnation line flow. In Pase II,
computational algorithm developed in Phase I would be applied to predict the complete
flowfield with wake closure on bodies of arbitrary shape.
This computer code would provide to the designer of space vehicles vital information
about the aerothermal environment of an aerobraking/reentry-type vehicle with wake
in the complete transitional regime.
rarefied gas, Navier-Stokes, slip, merged layers, wake

Project Title:

Effects of Supercooling and Melt Phenomena on Particulate Radiation in Plumes

02.05-0003
900636
Effects of Supercooling and Melt Phenomena on Particulate Radiation in Plumes

Abstract:

In the evaluation of radiative heat loading from solid rocket plume particulate radiation,
the effects of particle supercooling on the submelt radiative characteristics are
not well understood. This project will experimentally characterize this supercooling
phenomenon by observing particle radiation during the rarefaction wave cooling of
shock-heated Al2O3 particles. The Phase I effort will provide NASA with quantitative
data for the effects of supercooling on the optical properties of Al2O3, and will
define potential Phase II efforts to quantify other high temperature radiative effects
and to develop experimental concepts for verification of predictive codes. The innovative
aspects of the work lie in the use of the rarefaction-wave in a shock tube to simulate
plume supercooling effects and in the application of state-of-the-art optical diagnostics
to determine refractive indices of particles at high temperatures.
The diagnostic techniques and data bases would be relevant to the solid rocket motor
industry.
plumes, radiation, particulates, solid rocket fuels, Mie scattering, optical properties

Project Title:

Radiation from Advanced, Solid Rocket Motor Plumes

02.05-2008
900788
Radiation from Advanced, Solid Rocket Motor Plumes

Abstract:

Thermal loads created by the plumes of advanced solid rocket motors are not predictable;
such loads are currently obtained from experiment. Test data are correlated by postulating
plume temperature, shape, and emissivity; and heating rates are calculated with appropriate
view factors from this simplistic plume model. Although other extensive relevant
technology has been developed to describe infrared signatures and to calculate plume
flowfields and non-grey, scattering radiation, such technology cannot yet provide
accurate base-heating estimates. This project will develop a prediction method for
quantitatively evaluating the thermal radiation from solid rocket motors which does
not require any subsidiary test data. Verification would be accomplished with existing
data, so that the method could be used as a design tool for evaluating radiation
base heating for advanced, solid rocket motor configurations.
A preliminary design tool for predicting radiative heating from advanced solid rocket
plumes would be used by NASA, DOD, and/or their prime contractors to analyze plume
heating for IR decoy design studies.
rocket plumes, plume radiation, IR signatures

Project Title:

A Zonal Method for Modeling Flow Fields of Powered-Lift Aircraft

02.06-3304
900738
A Zonal Method for Modeling Flow Fields of Powered-Lift Aircraft

Abstract:

Advanced short takeoff/vertical landing aircraft are designed to use exhaust jets
directly to increase lift. Being able to numerically model the flow fields involved
in these designs would greatly improve the design process. This project will develop
a cost effective flow analysis tool for modeling powered-lift aircraft flow fields.
A key ingredient in the development of a practical flow analysis is the turbulence
model. The Phase I objective is to develop and validate a turbulence model that will
accurately and efficiently model the turbulence phenomena in flows with strong curvature
as encountered in powered-lift flows. A two-equation model coupled to an algebraic
Reynolds stress model will be investigated in the context of a three-dimensional
Navier-Stokes code. A sub-grid-scale model will also be examined. The models will
be tested by calculating a jet in ground effect with a crossflow with particular
attention on the ground vortex.
The proposed flow analysis tool would be directly applicable to the design and evaluation
of powered-lift aircraft concepts.
zonal method, coupled analysis, Navier-Stokes, potential flow, powered-lift aircraft,
turbulence

Project Title:

A Multiple Component Force and Moment Balance for Water Tunnel Applications

02.06-8228
901124
A Multiple Component Force and Moment Balance for Water Tunnel Applications

Abstract:

The development of a multi-component force and moment balance for applications in
low-speed flow visualization water tunnels is the goal of this project. The balance
will allow detailed flow visualization and force and moment measurements to be performed
simultaneously in a water tunnel, thus providing quantitative information prior to
wind tunnel tests. In addition to saving time and cost of testing, uncertainties
associated with differences in models, facilities, and test conditions are eliminated.
The balance can also provide a capability for complicated dynamic measurements which
are difficult to perform in a wind tunnel. The long-term objective is to develop
and test a six-component force/moment balance system and related calibration equipment
that can be manufactured and produced commercially for other water tunnel users in
this country and abroad. The primary goal of Phase I is to develop preliminary designs
for various components of a force and moment balance. Major improvement and refinement
efforts would be carried out in Phase II to develop and construct a prototype of
a final design, and extensive static and dynamic tests will be performed to verify
the performance of the system and also to develop techniques for various applications.
Present water tunnel users in the U.S. and abroad would have the need for conducting
force and moment measurements in their tunnels. A balance capable of performing static
and dynamic force and moment measurements should greatly increase the interest and
demand for water tunnels.
water tunnel force and moment balance, static/dynamic measurements

Project Title:

Aerodynamic Control of Aircraft Using Miniature, Rotatable Nose-Boom Strakes

02.06-8228A
901126
Aerodynamic Control of Aircraft Using Miniature, Rotatable Nose-Boom Strakes

Abstract:

The goal of this project is an innovative method of enhancing the controllability
of aircraft at moderate to high angles of attack by controlling the forebody vortex
flow with rotatable nose-boom strakes. The idea is to control the asymmetry of the
nose-boom wake by placing small, movable strakes on the nose-boom. The wake then
acts as a controlled perturbation on the forebody flow and subsequently dictates
the form of the forebody vortex asymmertry. A preliminary water tunnel study demonstrated
that the concept is highly promising. The nose-boom strakes provide effective controls
on the forebody vortices for AOA's from approximately 25o to 60o or above. Thus control
forces may be generated to augment the controls presently available on the F-16 or
other aircraft to allow the full capability of the aircraft to be utilized. The innovative
system can potentially be very small in size, relatively easy to implement and operate,
and effective over wide ranges of angles of attack and sideslip.
This control system could be retrofitted to the existing aircraft and/or incorporated
in the ones in future production.
rotatable nose-boom strakes, forebody vortex control

Project Title:

A Novel Polarization Preserving Fiberoptic Sensor for High Temperature Environments

02.09-2701
901530
A Novel Polarization Preserving Fiberoptic Sensor for High Temperature Environments

Abstract:

This project investigates a novel fiberoptic sensor for high temperature environments
in which each eigenstate in a polarization preserving fiber forms an interferometer
to sense the temperature and the other causes of optical path length changes, such
as strain and pressure. This fiberoptic sensor has the potential for superior performance
in high-temperature environments as compared to the dual-wavelength fiber sensor.
Many fields could be explored for potential applications such as automobiles, aircraft,
production lines, and construction.
fiber sensor, fiber optics, temperature sensor

Project Title:

High Resolution Optical Multichannel Transducer Array for Wind Tunnel Applications

02.09-7500
901334
High Resolution Optical Multichannel Transducer Array for Wind Tunnel Applications

Abstract:

For the accurate analysis of wind tunnel modeling, it is necessary to have precise
measurements of the pressure profiles over the model surface to better understand
the effects of short scale length turbulence. The development of a durable transducer
array capable of spatially resolved, real time pressure measurements will be conducted.
The innovative features of the optical, multichannel transducer array (OMTA) are
two fold. First, the signals are based on optical effects for fast response and high
resolution. Second, the transducer array will be fabricated using semiconductor manufacturing
techniques and will be coated with diamond-like films for protection against high-temperature,
corrosive wind tunnel conditions. Through the use of such a system, high temporally
and spatially resolved measurements may be made in hostile environments. The importance
of this innovation is its impact on aerospace research and in particular, as a powerful
new diagnostic for wind tunnel studies on scale models.
This transducer system could be marketed as a finished product to be applied to harsh
environment sensing such as automobile engines or combustion facilities.
transducer array, fiber optic, pressure profile, wind tunnel

Project Title:

Adaptive Nonlinear Polynomial Networks for Rotorcraft Cabin Noise Reduction

02.10-4400
901887
Adaptive Nonlinear Polynomial Networks for Rotorcraft Cabin Noise Reduction

Abstract:

This project addresses the use of adaptive nonlinear polynomial network prediction
and noise cancellation algorithms to reduce rotorcraft cabin noise and vibration
via active anti-sound techniques. In recent years, there has been a considerable
amount of work on the use of statistical signal-processing techniques to produce
anti-sound acoustic fields for reducing vibration and noise in enclosed spaces. These
basic techniques employ adaptive linear prediction algorithms to the noise field
as sensed from an array of speakers to cancel the predictable part of the noise in
the array. The adaptive linear prediction and control methods used in the reduction
of cabin noise for propeller-driven appear to be quite successful. Although the noise
field produced by a propeller can be will-modeled as a Gaussian process (and thus
linear prediction is optimum), rotor noise typically has significant impulsive components
and cannot be well-modeled as a Gaussian process. Therefore, nonlinear predictors
are needed to achieve the desired cabin noise reduction. The Phase I work emphasize
the development of polynomial network predictor architectures to minimize the noise
residuals from an array of sensors within the cabin. In Phase II, a more detailed
multiple-error noise abatement system will be designed and evaluated using actual
rotorcraft data.
This work could be applied to areas of noise reduction in aircraft cabins and vibration
reduction in airframes. In a more general context, the modeling and processing techniques
could be applied in nonlinear signal processing for speech processing, data transmission,
and seismic signal processing.
impulsive noise, adaptive nonlinear prediction, rotor impulsive noise, noise cancellation,
rotorcraft cabin noise cancellation, anti-sound, statistical signal processing, non-gaussian
signal processing

Project Title:

Gas Turbine Noise Reduction

02.11-8610
900358
Gas Turbine Noise Reduction

Abstract:

Reduction of gas turbine propulsion system noise, and associated vibrations, is an
important goal for future aircraft. The objective of this project is to use an innovative
methodology to identify and quantify the primary source of noise in gas turbine combustors
and use the results to identify a high-potential, noise avoidance concept. An innovative
unsteady flow model will be used to identify and quantify the fluid dynamic source
of noise, small-scale experiments will be run to confirm the model results, and noise
avoidance concepts will be identified and ranked. A best concept will then be selected
and recommended for further development under a Phase II effort.
The use of this concept in commercial and military aircraft will reduce noise and
vibration impacts on aircraft, improve their reliability and reduce maintenance costs.
noise, combustion, vortex, combustor

Project Title:

Experimental Investigation of Shape Memory Alloys for Use In Rotorcraft De-icing

03.01-0533
902141
Experimental Investigation of Shape Memory Alloys for Use In Rotorcraft De-icing

Abstract:

Systems
Increased readiness and safety demands being made on helicopters require an all-weather
capability. While several promising deicers have been developed for fixed wing aircraft,
the requirement still exists for a reliable de-icing system compatible with helicopter
blades. The ideal deicer must be small, require a minimum amount of interface hardware,
be able to operate efficiently on low power/voltage, and be able to survive leading
edge erosion effects. This project will develop a unique ice protection system that
is based on the capability of shape memory alloys (SMAs) to change dimension rapidly
and reversibly when current or heat is applied. Several methods to induce the shape
memory effect including inherent resistive heating of the SMA, or heat transfer from
an attached thermal couple or conventional electrothermal de-icing coil will be investigated.
Mechanical debonding is expected to take place in seconds versus minutes using only
a fraction of the power required for thermal debonding. Helicopter blades may be
the ideal application for shape memory deicers because of the small leading edge
area and availability of convective cooling to induce martensitic transformations.
Phase I includes design and test of a SMA helicopter blade deicer prototype for evaluation
of leading edge ice debonding performance.
A shape memory alloy de-icing system may be well suited for use on marine vessels
and advanced commercial transports.
shape memory alloy, de-icing, rotorcraft

Project Title:

Pilot Wx Advisor

03.02-1400
901832
Pilot Wx Advisor

Abstract:

The safety of flight operations of many General Aviation (GA) aircraft is compromised
by the lack of real-time, severe weather information in the cockpit. This project
will develop and demonstrate an automated cockpit weather display system that will
do all these things and more. In Phase I, the ability of modern communication systems
to put large amounts of weather data derived from ground observing sites on board
a GA aircraft will be evaluated. Demonstration flight tests will be conducted to
show the feasibility of a satellite communication link and the prototype map-type
weather depictions. In Phase II, a prototype airborne system would be constructed
and tested on a high performance GA aircraft. Additional data types will be considered,
including area forecasts and trends, route cross sections, TDWR, and NEXRAD products,
if available, on an electronic, moving-map display. These additional data types will
be used as input to an on-board Smart System that would develop flight path recommendations
based on the Pilot's own operational criteria.
The potential market for a state-of-the-art cockpit weather display is conservatively
estimated to be 5000 units for existing aircraft, and 400 to 500 units a year for
new production.
hazardous weather, cockpit weather display, pilot weather advisor

Project Title:

Ideal Flying Qualities for Aero-Space Craft

03.03-2233
900490
Ideal Flying Qualities for Aero-Space Craft

Abstract:

There is currently considerable interest, both in the U.S. and abroad, in the development
of aircraft capable of hypersonic flight. However, there is very little guidance
available on the flying qualities characteristics which are desirable for this class
of vehicles. This project will attempt to determine the most ideal set of flying
qualities characteristics by using a key result of integrated control system technology.
Future hypersonic aircraft will no doubt require the use of an integrated control
system which will integrate the aircraft's aerodynamics, propulsion, and stabilization
system. Using an integrated, model-following control system, it is possible to make
the aircraft response match that of a chosen command mode.  Therefore, this project
will seek for the optimal command mode for hypersonic aircraft. This innovative approach
is in direct contrast to the traditional method of closing one control loop at a
time until "acceptable" flying qualities are achieved. The Phase I work will focus
on a review of current applicable flying qualities criteria, construction of a preliminary
command model, and development of a simulation test plan. The Phase I work will serve
as preparation for a real-time, piloted simulation of the command model dynamics
in Phase II.
Commercialization of the ideal command model description will result from technology
transfer to airframe manufacturers currently interested in developing manned, hypersonic
aircraft. The technology will be transferred by marketing software for comparison
of vehicle characteristics to the ideal.
hypersonic, flying qualities, flight control

Project Title:

Visual Motion for Rotorcraft Guidance

03.04-7300
901128
Visual Motion for Rotorcraft Guidance

Abstract:

For rotorcraft in a nap-of-the earth (NOE) flight regime, collision with wires presents
a significant threat to safety. Wire detection and avoidance is thus an important
part of safe NOE guidance. Wire detection can be difficult because:  wires are often
not strongly spatially evident, dangerous wires often occur at the focus-of-expansion
(FOE), there is often significant background clutter and noise, and the detection
task is on-going and must be fast enough to permit evasive maneuvers. This effort
examines innovative wire detection and tracking techniques that address these issues.
Wires are treated as moving edges in densely sampled imagery, and these edges are
then traced using local computational mechanisms that are amenable to fully parallel
implementation with VLSI. Tracker control methods will be explored which integrate
numeric information from known parameters of camera motion produced by gyros with
symbolic and rule-based information based upon aggregates of image features in order
to improve tracking and compute motion properties. These tracked edges provide important
descriptions of moving wires (e.g., measures of stability and motion) which can be
used for avoidance and guidance.
An automated wire avoidance system has direct applicability for commercial air traffic
safety. This project also provides a basis for developing advanced vision guided
robotic capabilities.
vision-guided navigation, wire detection and avoidance, moving edge detection, tracking,
parallel vision algorithms

Project Title:

A Compact Optical Air Data System for Flight Test Applications

03.05-3636
900731
A Compact Optical Air Data System for Flight Test Applications

Abstract:

An innovative electro-optical primary, air-data system concept that will provide
accurate airspeed, angle of attack, and angle of sideslip information will be evaluated.
Patented technology will allow a compact, lightweight, and eye-safe laser velocimeter
system to be constructed for airborne use. Phase I of the program will involve preliminary
flight testing of an existing proof-of-concept prototype unit to establish suitability
as a primary, air-data flight test instrument. Phase II is contemplated to expand
the flight envelope into the supersonic and high angle regimes with a fully capable
prototype system
In addition to flight-test measurement applications, this technology is valuable
in both commercial and military markets as both a primary air-data system for high-performance
aircraft as well as a "look-ahead" wind shear detector.
primary air data, electro-optics, laser doppler velocimetry, LIDAR

Project Title:

In-Flight Flow Velocity Sensor

03.05-6100
900147
In-Flight Flow Velocity Sensor

Abstract:

Existing airspeed sensors are bound to the airframe surface, and sample the flow
within the bow wave perturbation zone where airspeed and angle of attack information
are intermixed. This innovation combines recently developed technologies that enable
flow measurements off the airframe surface in the free stream beyond the bow wave.
Narrowband diode laser technology coupled with high power laser diodes and an innovative
double heterodyne detection system enables measurement of the Doppler shift of the
laser light backscattered from the aerosol content of the atmosphere. Three such
sensors can be used to determine the magnitude and vector direction of the air velocity,
yielding both airspeed and angle of attack. With a small addition in electronics,
an ice/snow discriminating detector could also be added to the system to warn of
dangerous levels of ice crystals in the freestream. This system will be all-solid-state
and, therefore, compact, efficient, and rugged enough for the inflight application.
The available dynamic range extends from low speed to Mach 18, depending on the electronics
design. The Phase I objective is to measure the signal-to-noise ratio of a breadboard
system.
After initial inflight testing to establish airframe performance envelopes, the sensor,
if the cost is low enough, could be used in general commercial aviation to optimize
fuel usage.
airspeed, angle-of-attack, compact, efficient, ice, laser, velocity

Project Title:

Non-Intrusive Boundary Layer Transition Frequency Detector

03.05-8100
900165
Non-Intrusive Boundary Layer Transition Frequency Detector

Abstract:

A non-intrusive boundary layer transition detector that can indicate the presence
of local transition and provide information on the frequency components of the flow
will be developed. The design concept is an adaptation of a transition detector used
successfully in ballistic missile reentry vehicle flights. The work will demonstrate
concept feasibility on flight skins of present interest to NASA. A study will be
performed to provide data for modeling the transitional and turbulent boundary layer
pressure spectrum. An evaluation of acoustic noise sources which may affect gage
performance and method for addressing them will be made. A preliminary heat-resistant
design will be constructed and tested in the laboratory for localized and frequency
response. Methods for improving gage ability to respond to only local signals will
be identified. A flight test program will be specified for evaluating gage performance
in a NASA field testing.
This gage would be useful instrumentation for many commercial firms and researchers
interested in transition experiments or any turbulent boundary layer experimentation.
Such development as the National Aerospace Plane and Supersonic Transport could use
the device to monitor the success of transition delaying techniques.
non-intrusive, boundary layer transition, acoustic sensor, piezoelectric

Project Title:

Compact Rugged Laser Doppler Velocimeter Probe for In-Flight Gas Turbine Inlet Flow

03.06-0321
901176
Compact Rugged Laser Doppler Velocimeter Probe for In-Flight Gas Turbine Inlet Flow

Abstract:

Measurements
Measurements of the inlet flow fields of aircraft propulsion systems are important
in defining the thrust and efficiency of these engines as well as to flight safety
when executing avoidance maneuvers. This project will develop a non-intrusive laser
Doppler velocimeter (LDV) probe that is compact and rugged enough to perform these
measurements in-flight. This LDV probe will replace the more intrusive and bulky
material probes currently in use. Mapping the inlet flow velocity will allow more
accurate measurement of in-flight thrust as well as aid in the understanding of inlet
stall and separation. This probe is only now possible with recent developments in
fiber optics and frequency domain signal processing. This project involves the definition,
design, and preliminary testing of an innovative probe to measure these inlet flow
fields. Size discrimination of seeded particles will be included so that atmospheric
aerosols can be used as seed particles. Testing of the prototype probe will be conducted
both in simulated and ground, tethered flow fields.
Beyond the measurement of inlet flow field of gas engines, this has commercial applicability
to numerous other flow fields such as power plants, rocket engines, and virtually
any fluid dynamic flow with harsh conditions.
laser doppler velocimeter, gas turbine inlet

Project Title:

Carbon-Carbon/Refractory Metal Heat Pipes for Leading Edge Cooling on Reusable Hypersonic

03.07-0236
900799
Carbon-Carbon/Refractory Metal Heat Pipes for Leading Edge Cooling on Reusable Hypersonic

Abstract:

Vehicles
Reusable hypersonic vehicles, operating well beyond the performance envelope of conventional
aircraft, will encounter extremely high temperatures; during reentry, the nose will
experience in excess of 5000oF, and leading edge surfaces will feel nearly 3500oF.
Clearly, lightweight leading edge cooling concepts are needed to withstand such high
temperatures. The heat pipe, a quasipassive, self-contained, low-maintenance device,
should be well-suited for leading edge cooling applications. In this Phase I program,
this project will demonstrate the feasibility of fabricating a straight D-shaped
heat pipe by chemical vapor deposition (CVD) and infiltration (CVI). The wick will
be a refractory metal-infiltrated carbon foam, and the container walls will be a
thin refractory metal skin or shell. Compatibility of the chosen refractory metal
with carbon-carbon will be established, and CVD technique for producing container
walls of minimum thickness for weight reduction will be defined. At the end of the
project, the heat pipe will be filled with a working fluid and tested for isothermal
operation. The result will be the definition of techniques for fabricating actual
leading edge heat pipe configurations in Phase II and beyond.
Lightweight, refractory metal heat pipes would apply to the wing leading edges of
reusable hypersonic vehicles such as the NASP.
heat pipes, leading edge cooling, reusable hypersonic vehicles, foams, refractory
metals, carbon-carbon composites, chemical vapor deposition/infiltration, NASP

Project Title:

Passive Propeller Control

03.08-9983
901863
Passive Propeller Control

Abstract:

Very high altitude, long endurance (VHALE) type aircraft operate over a wide power
range due to altitude and fuel load changes. Matching the propeller to the engine
over this range is difficult without a complicated variable pitch propeller or gearing.
Passive optimal pitch control is the goal of this project. The concept consists of
a aerodynamically tailored blade, balance weights, and torsionally soft spar mounted
on the main propeller shaft and attached to the blade at a point near its mid span.
This eliminates most or all of the linkages and bearings normally needed in a variable
pitch mechanism achieving substantial weight savings and increased reliability. The
problem of simple inertial/aero/elastic control is that, over a wide operating range,
the required setting is difficult to achieve passively. A method for the multi-point
optimal design of passive pitch control propellers which deals with the matching
problem will be applied. The tasks include determining design requirements, developing
a computer design method for the blade pitch dynamics, exercising the method to design
a specific passive pitch propeller mechanism, and evaluating the merits of this concept.
The commercial applications of the design concept and methodology would be in VHALE
and other UAV and light plane applications.
VHALE propulsion, passive pitch control, constant speed propeller

Project Title:

Knowledge-Based Tools for the Conceptual Design of Human-Machine Systems

03.09-1457
901254
Knowledge-Based Tools for the Conceptual Design of Human-Machine Systems

Abstract:

While current technology has made the automation of many crew functions feasible,
the human's capabilities, limitations, and preferences may make automating certain
functions undesirable. Designers initially make function allocation decisions during
the conceptual design of human-machine systems. There are currently no knowledge-based
tools available that support the designer in making these decisions. These decisions
define the nature of the human's role in the system and determine the potential performance
levels that can be achieved with the system. A large percentage of the life cycle
costs of a system are also determined by decisions made during conceptual design.
The design tools to be developed in this project will support the designer in defining
and allocating the system's functions; evaluating the human's functions and tasks
by examining the capabilities, limitations, and preferences of the human; and suggesting
methods for overcoming the limitations and enhancing the capabilities of the human.
This effort will determine the nature of the support that the designer needs, identify
design and knowledge representations for the tools, and develop a scripted prototype
to demonstrate and evaluate the tools.
Knowledge-based tools that support the conceptual design of human-machine systems
have the potential for wide application in aviation, manufacturing, process, and
power industries.
tools, conceptual design, human-machine systems, function allocation

Project Title:

Applying Recognition-Primed Decision Making to Man-Machine Interface (MMI) Design

03.09-2691
901437
Applying Recognition-Primed Decision Making to Man-Machine Interface (MMI) Design

Abstract:

Flight mission operations can require decision making under conditions--time pressure,
psychological stress, poor information, uncertain communications--that make careful
analysis difficult. Recent research on strategies of experienced decision makers
in complex operational tasks has generated such descriptive accounts as the Recognition-Primed
Decision (RPD) model, showing why prescriptive decision support systems (DSSs) are
poorly received in the field. Under pressure, experts use experience to generate
a likely course of action. The goal of this project is to build on recent research
with the RPD model for designing more effective DSSs and man-machine interfaces (MMIs).
It should also generate three sets of engineering design principles, one for identifying
the critical decisions within a mission, a second for defining the boundary conditions
of different decision strategies, and the third will address the use of the RPD model
for DSS and MMI design.
The research could apply in a variety of domains (e.g., air traffic control, process
control, as well as aviation) where there are needs for operators to respond quickly
to emergency conditions.
man-machine interface, human-computer interaction, decision support system, decisions,
decision making, user-computer interface, stress

Project Title:

Applications of Artificial Intelligence to NASP

03.10-7212A
901676
Applications of Artificial Intelligence to NASP

Abstract:

This project explores the applicability of expert system technology to the National
Aerospace Plane (NASP). It will investigate the feasibility of developing real-time
cooperating, distributed expert systems executing in either on-board or ground based
computers (or both) to perform a variety of functions. The functions include mission
planning (including real-time replanning);  system monitoring, diagnostics and management;
and trajectory management and control. Prudent application of this branch of artificial
intelligence to NASP will improve the platform's operational versatility, adaptability,
and effectiveness. Specific potential improvements include an on-board capability
of adjusting a mission plan in real-time in response to a system failure or degraded
performance, an on-board capability of monitoring and providing diagnostics for NASP
subsystems, and preflight planning passed on the automated flight test management
system. Expert system technology is particularly suited to abort trajectory management,
propulsion system monitoring and diagnostics, and flight test planning.
Extensions of this work could apply to planet surface and atmospheric explorers (such
as the Mars Rover), military reconnaissance vehicles, and others.
expert systems, planners, monitoring, diagnostics, trajectory

Project Title:

A Finite Element Heat Transfer Analysis System for Simulation of Flight Vehicles

03.11-1679
900210
A Finite Element Heat Transfer Analysis System for Simulation of Flight Vehicles

Abstract:

Predicting the performance of a hypersonic aerospacecraft such as the National AeroSpace
Plane (NASP) is difficult because of current technological limitations. Wind tunnels
to run high Mach flights to get data on airflow, roll rate, and shock structures
are not available. Numerical simulation based on the finite element solution technique
offers a viable, rapid and accurate approach for predicting flight characteristics
needed for design, for interpreting flight test results, and for ensuring safety
during flight envelope expansion. Such flight characteristics are highly nonlinear
and complex due to inherent interactions of several constituent disciplines such
as structures, heat transfer, materials, fluid dynamics, controls, propulsion, and
others. Further, the relevant analysis requires extensive supercomputing effort.
Consequently, several essential disciplines as well as efficient solution techniques
will be incorporated in an integrated vehicle flight simulation system. Phase I activities
will focus on developing methodologies for nonlinear heat transfer simulation capabilities.
The development of a complete heat transfer analysis system as well as efficient
algorithms for capturing shocks, separated flows and vortices in hypersonic flows,
and adaptive and automatic mesh generation techniques will be addressed in Phase
II.
An integrated numerical simulation system can be used to solve a wide spectrum of
problems in almost all branches of engineering including aerospace, civil, mechanical,
electrical, automotive, petrochemical, bio-medical, and space engineering.
FEM, heat transfer, CFD, flight characteristics, aerospacecraft simulation

Project Title:

Solution-Adaptive Code For Analysis Of Fatigue Crack Propagation In Aerospace Structures

04.01-8122
9000082
Solution-Adaptive Code For Analysis Of Fatigue Crack Propagation In Aerospace Structures

Abstract:

This project will develop solution-adaptive techniques and a computer code for use
in analyzing fatigue crack propagation in aerospace structural components. A fracture
analysis computational tool will be created using modern adaptive finite element
techniques, extraction formulas and crack propagation theories. The code will be
virtually a stand-alone module in that no additional structural modeling will be
required other than a description of the material flaw.  It will be developed as
a post processor to existing finite element program packages. The finite element
model of the unflawed structure will be prepared in the same manner as is currently
done. Flaws can be introduced into these existing finite element models and the fracture
analysis performed virtually transparent to the user. The stress analyst can then
perform a fracture mechanics analysis with very little additional effort. The Phase
I study will focus on solution-adaptive algorithm development and will utilize stress
intensity factor calculations for fatigue life prediction. The Phase II study will
include research and development into constitutive theories of fracture, accurate
stress recovery procedures, adaptive refinement strategies, and development and delivery
of a general three-dimensional code
The computer code will be valuable to aerospace, mechanical and civil engineers in
all disciplines. Among the numerous commercial applications are design of high rise
buildings, analysis of damaged buildings, structural fatigue analysis of commercial
airplanes, and safety analyses of automobiles, bridges and highways.
fracture mechanics, fatigue crack propagation, finite elements

Project Title:

Real Time Monitoring of Material Degradation of Fiber Composites

04.01-8200
901048
Real Time Monitoring of Material Degradation of Fiber Composites

Abstract:

A novel approach for the on-line monitoring of degradation of composite material
will be investigated. This approach utilizes the dynamic response characteristic
of the composite components and a pattern recognition method. The dynamic responses
of a perfect and a degraded component can be simulated through a finite element analyses.
The results can be used in a training/learning exercise through an expert system
to classify the degradation status of other similar components. This approach will
provide an efficient means of assessing qualitatively the well-being of the component.
This approach can provide an efficient means for the quality control and on-line
monitoring of composite components in aircraft.
real time monitoring, fiber composites, stiffness, residual strength

Project Title:

Thermo-Chemical Structural Analysis of Carbon-Phenolics With Pore Pressure and Pyrolysis

04.01-8900
900006
Thermo-Chemical Structural Analysis of Carbon-Phenolics With Pore Pressure and Pyrolysis

Abstract:

Effects
Carbon-phenolic (c/ph) composites have been widely used in solid rocket motors, despite
the fact that their high-temperature, thermostructural behavior is not well understood.
Many of the failure modes (e.g., wedge-out, ply-lift, delamination, pocketing) commonly
seen in the c/ph components of fired SRM nozzles can only be explained as pore-pressure-induced
phenomena that occur during pyrolysis. Yet, none of the current thermostructural
analysis methods are capable of accurately predicting the high heating rate behavior
of simple c/ph test specimens, let alone accurately characterizing the pore pressure
and pyrolysis behavior of an actual motor nozzle. This project addresses the problem
of accurately characterizing the thermostructural behavior of c/ph subjected to a
high-temperature and heating-rate environment as typically found in a solid rocket
motor. This will be accomplished by a method which couples the thermo-chemical to
the thermostructural analysis by using a volume-based continuity model. This unique
approach models the pore-pressure development during pyrolysis more accurately than
current analytical methods since it couples the pore-pressure level directly to the
structural deformations.
The development of an accurate thermostructural analysis method for carbon-phenolic
materials is s\extremely important to increasing the performance, reliability, and
level of confidence in the design of large solid rocket motors.
carbon-phenolic, pyrolysis, pore pressure

Project Title:

Method for Producing Ultra-Pure Titanium Aluminide Wire for Arc-Spray Feed

04.02-4888
901983
Method for Producing Ultra-Pure Titanium Aluminide Wire for Arc-Spray Feed

Abstract:

Metal-matrix composites are being considered as exceptionally useful materials to
replace very high performance, light-metal alloys and super-alloys for very high
trust-per-pound aircraft propulsion devises. There are many manufacturing difficulties
with these materials, however. The consolidation of continuous fiber reinforcement
with the matrix into a useful intermediate product such as tapes ia a major one.
One particularly attractive way of doing this is by the use of arc-spray transport
of the intermetallic material. Such a process requires an uncontaminated wire feed
material. Manufacture of such a wire by conventional means if very difficult, if
not impossible. This work covers an effort to show the feasibility of making an ultra-high-purity,
intermetallic wire material by chemical vapor deposition of titanium aluminide on
a very small, high purity, seed wire. Not only does this provide a convenient way
of making the wire without conventional drawing problems, but offers the prospect
of eliminating the problem of interstitial contamination.
A better method to make the tape intermediate for metal matrix composite bodies would
allow MMCs to replace a large percentage of high performance light metal and super
alloys for gas turbines and other applications.
metal matrix, titanium aluminide, intermetallic wire

Project Title:

The Development of FeBe5 Fiber Using a Dual Plasma Deposition System

04.03-1980A
900704
The Development of FeBe5 Fiber Using a Dual Plasma Deposition System

Abstract:

New fibers are needed to produce intermetallic composites for use in aero and space
propulsion systems because existing fibers do not have adequate thermochemical stability
in desirable structural materials such as iron aluminide. FeBe5 has been predicted
to have thermochemical stability in iron aluminide and would be a desirable reinforcement
if it could be produced in a fibrous form with high strength. A new dual plasma process
has been developed that has the ability to deposit FeBe5 and other difficult-to-deposit
materials at high deposition rates. The dual plasma process will be utilized to develop
the deposition of FeBe5 into oxide fiber substrate producing fiber diameters up to
75u. The FeBe5 fibers will be characterized for mechanical properties and compatibility
in an iron aluminide matrix.
Iron beryllide fibers, predicted to be thermochemically stable in iron aluminide,
other intermetallics, and metals, could be applied in composites for a wide variety
of aero and space propulsion systems and aerospace structures as well as tools, dies
and general structures.
iron beryllide, intermetallics, fibers, beryllium intermetallics

Project Title:

High Performance, Textile Grade, Micro-Laminate fibers

04.03-4888A
901982
High Performance, Textile Grade, Micro-Laminate fibers

Abstract:

A technique has been devised to make high-operating-temperature, ceramic, micro-fibers
by chemical vapor deposition of a silicon carbide ultra-structure on a filamental
seed. Chemical vapor deposition for making fibers is old art, but the fibers produced
were always macro-fibers, some of which have performed very well because of the very
high strength of the deposited material. The approach taken in this project makes
use of CVD techniques to deposit a micro-laminated structure, wherein the laminates
do not exceed 50 nm in thickness. Great toughness is expected from these fibers.
Because of their small diameters they will be textile-grade fibers. Additionally,
barrier coatings will be applied as the final laminate without interruption of the
process.
Successful completion of this project should provide improved, micro-fibers for light-weight,
erosion, and oxidation-resistant metal-matrix and ceramic-matrix composites for aerospace
vehicle and engine use.
ultra-structures, micro-fibers, metal-matrix, ceramic-matrix

Project Title:

Coated Graphites Fibers for Highly Conductive Composites

04.03-8080
901936
Coated Graphites Fibers for Highly Conductive Composites

Abstract:

Copper/graphite composites offer a unique combination of high thermal conductivity
and high temperature strength and modulus. They are particularly useful for thermal
management for space power generation. However, because molten copper does not wet
graphite, hot pressed copper/graphite composites are not thermally stable, developing
pores and swelling when exposed to high temperature environments. The purpose of
this project is to develop a reliable and reproducible coating process for graphite
fibers which would allow the fibers to be wet by molten copper. Not only will it
improve the thermal stability of the composite, but it will be easier to produce
complex forms and structures by means of the air stable coating. The coating is compatible
with other metals, such as aluminum, allowing the same coating to be used to produce
aluminum/graphite composites.
The high conductivity of the composite may be useful as a heat sink for high power
integrated circuits. Other composites which would be developed in future research
such as aluminum/graphite would be useful for aerospace structures.
composite, fiber coating, copper, graphite, thermal management

Project Title:

Innovative Fiber Laser Furnace

04.03-8476
900593
Innovative Fiber Laser Furnace

Abstract:

The innovative fiber laser furnace offers the opportunity for new technology in the
single crystal fiber testing laboratory. Single crystal fiber research involves the
production of new single crystal fibers with subsequent strength testing. Extensive
testing requires heating the fiber to the operational temperatures of the fibers
application. IN this case, one encounters problems associated with the heating of
a small mass which is surrounded by a large massive testing machine. Typically, use
of bulk-type resistance heaters requires large electrical input powers to reach the
testing temperatures. These heaters also heat up the fiber clamps and surrounding
machine and increase the difficulty of the measurement. This project investigates
a laser-heated furnace to facilitate the testing of aerospace fibers.
This product would provide for the upgrading of fiber testing machines to enhance
measurement capabilities.
fiber, testing, aerospace materials, composite fiber testing

Project Title:

Protective Refractory Alloy Composite Coating Using Novel LTAVD Technique

04.04-1980
900705
Protective Refractory Alloy Composite Coating Using Novel LTAVD Technique

Abstract:

There is a critical need to eliminate the severe restrictions imposed on the use
of many alloys in advanced propulsion systems due to hydrogen embrittlement and oxygen
instability. The application of a stable coating which could protect the alloy from
these environmental hazards would substantially improve the efficiency and performance
of the components in these systems. It is proposed that this can be achieved with
the application of a Zr02-TiC alloyed composite coating of a possibly graded composition.
Zr02 has a thermal expansion coefficient approaching that of metals (reducing thermal
stress), and the Zr02-TiC material has previously exhibited low wear at both low
and high temperatures. This coating will be deposited using a novel coating approach
in which the ceramic composite is used as the cathode in an electric arc discharge
mode. The proposed technique is innovative in that the materials are deposited at
very high kinetic energies which results in excellent adhesion and a high rate of
deposition. In addition, this will involve the deposition of multicomponent refractory
materials without the introduction of a significant amount of heat to the substrate.
The successful application of low temperature coating of multicomponent refractory
composites could be applicable for propulsion system components, aerospace components,
engine components, cutting tools, and wear parts.
plasma, composites, coating, advanced propulsion systems

Project Title:

Environment-Resistant Coatings for Ti-Alloys

04.04-5200
900859
Environment-Resistant Coatings for Ti-Alloys

Abstract:

The NiCoCrAlY compositions are extensively used for oxidation protection of Ni-base
superalloys. However, for higher temperature Ti-alloys, this overlay will react with
the substrate thus defeating the intended purpose of the coating. This project explores
the development of a composite coating where an intermediate NiTi layer is interposed
between the titanium alloy and the NiCoCrAlY overlay. The ductile NiTi layer can
accommodate interfacial stresses generated due to the thermal expansion mismatch
between the base material and the protective coating. In addition to NiTi being compatible
with titanium, it is expected to be compatible with the NiCoCrAlY layer as well.
The establishment of this composite coating approach will result in a rather quick
and easy adaptation of the well examined and applied NiCoCrAlY coating to titanium
alloys thus enhancing their capability for high performance gas turbine applications.
Applications would be in structural and gas turbine engine applications where higher
operating temperatures can result in significantly higher thermal efficiencies and
where an improved environmental resistance can significantly improve the in-service
life of the component.
oxidation resistant coatings, environment resistance

Project Title:

Enhanced Computational Structural Methods for Aerospace Applications

04.05-2380
900199
Enhanced Computational Structural Methods for Aerospace Applications

Abstract:

Two methodologies for increasing the efficiency and effectiveness of computer analysis
of aerospace structures will be addressed. The approach is the use of functional-link
neural-net technology for generalization of quantitative analysis results so as to
circumvent the need for extensive time-consuming reanalysis and the use of the episodal
associative memory for capturing design experience for the guidance of subsequent
designs. The functional-link net methodology is a neural-net technology developed
by the firm and is particularly useful for learning functional relationships and
for providing accurate quantitative estimates in response to designs and for converging
in on optimal designs. The episodal associative memory is a computer architecture
for organizing and storing experimental knowledge which can be retrieved associately
in response to new tasks. This additional functionality can be effective in directing
the creation and analysis of a new design.
The resulting computer soft-ware systems will greatly enhance the power of all finite-element
analysis tools and optimal design tools. This technology will find use in essentially
all computer design aids offered commercially.
aerospace, structures, analysis, optimal-design, neural networks, associative -memory

Project Title:

A New Machine Architecture for Structural Analysis

04.05-8166
900156
A New Machine Architecture for Structural Analysis

Abstract:

A fast novel scientific workstation is proposed for solving aeropropulsion system
structures with cyclic symmetry exhibiting nonlinear response in high temperatures.
An engineering study will map efficient algorithms onto new parallel architecture
which is extensible across both the SIMD and MIMD design paradigm. A significant
feature of the approach is the coupling of the same computational kernel to several
processing elements so that true parallel computing without usual data partitioning
overhead occurs. A fully parallel single instruction/clock crossbar ASIC is to be
implemented for the dynamically reconfigurable architecture. This achievement is
now possible only through recent VLSI discoveries with ASIC devices. Because the
computer hardware "glue logic" has shrunk, physical boards and backplanes have also
reduced to make economic designs at 200 MHz clocks feasible.
This fast architecture is attractive to several biomedical applications including
MRI, CATSCAN, PETSCAN, and Ultrasound imaging because the efficient parallel algorithms
and data streaming speeds reduce both computation time and hardware costs.
multiprocessor, SIMD, MIMD, SVD, crossbar, vector, scientific workstation

Project Title:

Pressure Infiltration of Net-shape Graphite Preforms for Metal Matrix Composites

04.06-1477
901698
Pressure Infiltration of Net-shape Graphite Preforms for Metal Matrix Composites

Abstract:

Much of the cost of advanced composites is due to fiber handling and consolidation.
These "fiber placement" costs rise as the shape of the component becomes more complex
and as the number of reinforced directions increases.  This project will examine
a new method for producing three-dimensional, carbon-reinforced metal matrix composites.
All fiber handling steps are eliminated through the use of a new preform material.
This novel material is produced by in-situ creation of vapor grown carbon fiber (VGCF)
upon a molded carbon scaffold. VGCF has a unique morphology which may act as a mechanical
fuse to improve composite toughness. Although produced from inexpensive hydrocarbon
gases, VGCF's properties approach those of single crystal graphite, including a modulus
of 87 MSI, strength of l.0 MSI, and thermal conductivity of l950 W/m K. Metal matrix
composites will be fabricated using a pressure infiltration technique developed by
James Cornie, Director of the Laboratory for Inorganic Composites at MIT.
Commercial applications include low-cost metal matrix composites for high performance
structural and thermal management applications. Specific commercial components include
electronic heat sinks and packaging material and space-based thermal radiators.
metal composite, carbon graphite, net-shape, thermal

Project Title:

Development of Synergistic Prepregging Technologies

04.06-3200
902079
Development of Synergistic Prepregging Technologies

Abstract:

High performance, thermoplastic (TP) resins are notoriously difficult to melt-prepreg
because of their high viscosities, and high modulus fibers for advanced composites
are difficult to handle and melt-prepreg. Two innovative prepregging technologies
will be combined with advanced fiber/matrix materials to form prepregs that provide
superior structural efficiency and excellent high temperature performance. These
synergistic technologies are high shear prepregging (HSP) and maximal fiber spreading
(MFS). HSP technology dramatically reduces TP resin viscosities by shear-thinning
and readily accomplishes complete fiber impregnation. Current commercial prepregging
technology yields prepregs with minimum fiber areal weights (FAWs) of only 90 g/m2.
Foster-Miller's MFS technology will be able to achieve FAWs of 30 g/m2. Combining
these two technologies will result in ultrathin, high performance thermoplastic prepreg
which will provide significant structural weight savings and enhanced performance
in aerospace applications. This Phase I effort will demonstrate the synergistic prepregging
technologies by designing and fabricating a small-scale demonstration MFS system
which will be used in conjunction with HSP technology to produce high quality Gr/LaRC-TPI
prepreg with a FAW <35 g/m2. This prepreg will be molded into laminates for SEM,
tensile testing, and sampling to NASA.
Ultrathin (l mil thickness), high performance TP prepreg can be used with automated
fabrication methods to make aerostructure components for commercial applications
like the high speed civil transport, tubular members for space structures, and ultralightweight
beam structures.
thermoplastic, fiber spreading, LaRC-TPI, graphite fiber, advanced composites, high
temperature performance, lightweight structures

Project Title:

Protective Coating for Carbon-Carbon Composites

04.06-6000
900228
Protective Coating for Carbon-Carbon Composites

Abstract:

Carbon-carbon (C-C) has an extremely high strength-to-weight ratio and would therefore
be the material of choice for hot structures on hypersonic vehicles if its oxidation
resistance could be improved. To achieve this objective a coating system will be
developed in which a very thin film of platinum serves as the final line of defense
against oxidation. Platinum has a high melting temperature, excellent oxidation resistance,
and is ductile enough to avoid cracking during thermal cycling. To assure good adhesion,
the platinum film will be formed on C-C by ion beam assisted deposition (IBAD). IBAD
will be used in Phase I to platinum coat two-dimensional (2D) C-C coupons; the coupons
will be evaluated for oxidation resistance up to 2500oF during thermal cycling. Successful
Phase I results will lead to fabrication and testing of C-C panels with platinum
films forming part of an oxidation-resistant coating system. The platinum film will
be one component of a system incorporating matrix oxidation inhibitors, ceramic surface
coatings, and glassy crack sealers--resulting in multiple lines of defense against
composite oxidation.
Successful development of oxidation-resistant coatings for C-C composites would increase
the lifetime of aerodynamically heated surfaces of high performance aircraft and
hypersonic vehicles and turbine and rocket engine components. Additional applications
include furnaces for drawing glass fibers and hot tooling in the steel industry.
coatings, carbon-carbon composites, oxidation resistance, platinum

Project Title:

Remotely Deployable Self-Rigidizing Composite Space Structures

04.06-9709
900663
Remotely Deployable Self-Rigidizing Composite Space Structures

Abstract:

Major design and cost factors in space structures are deployment and dimensional
stability. These are particularly important considerations for large space structure
assemblies associated with the space station, space platforms, large deployable antennas,
solar energy collectors, and many other applications. Innovative space structures
that utilize lightweight non-metallic, high-strength, reversible and nonreversible
polyimide composite materials will be evaluated to determine their feasibility for
remote deployment and self-rigidization. The polyimides to be evaluated were developed
for enhanced resistance to the space environment. The composite materials fabrication
process will be refined and structural elements will be fabricated and tested individually
and in a proof of concept deployable structure configuration. The results of this
research will demonstrate the feasibility of deployable space structures of superior
characteristics.
This technology has commercial application in space platforms, large satellites,
and satellite servicing operations.j
space structures, self-rigidizing, polyimide composite, lightweight

Project Title:

Advanced Powder Synthesis for Improved High Temperature Light Alloys

04.07-0236
900788
Advanced Powder Synthesis for Improved High Temperature Light Alloys

Abstract:

This project will demonstrate the feasibility of a unique new method for producing
dispersion-hardened alloys. Dispersed, stable second-phase particles having a controlled
morphology will be incorporated into matrices of aluminum and titanium alloys. This
will be accomplished by coating each particle of the matrix powders with titanium
diboride (TiB2) by chemical vapor deposition (CVD), followed by milling/grinding
to disperse the second phase into the particles. Successive coating/milling steps
will guild up the  desired volume fraction of dispersed second phase (=20%), followed
by consolidation. Additionally, TiB2 reinforcement particles will be coated with
titanium and aluminum and then consolidated. The combination of CVD coating and mechanical
alloying to provide an intimate mixture of a dispersed second phase will result in
an innovative advance in metal-matrix composite processing while effectively eliminating
problems of homogeneous mixing, distribution of second phase particles, and contamination
by impurities. This process will also address current needs for advanced composite
materials having low density, high specific strength and modulus, high damage tolerance,
and resistance to microcracking when exposed to long-term thermal cycling.
This process for incorporation of new strengthening and stiffening phases in light
metal alloys and intermetallic materials is directly scaleable to production quantities
while the properties of the dispersed phase (particle size, volume/weight fractions)
will be controllable and repeatable over wide ranges.
metal matrix composites, titanium diboride (TiB2), light alloys, aluminum, titanium,
strengthening, chemical vapor deposition (CVD), dispersion hardening

Project Title:

Novel Higher Temperature Aluminum Alloys by Rapid Consolidation of Glassy

04.07-1933
901318
Novel Higher Temperature Aluminum Alloys by Rapid Consolidation of Glassy

Abstract:

NASA has interest in new aluminum alloys of non-equilibrium chemistries with the
objective of increasing the upper use temperature by 200F. Prior art has dealt with
the use of rapid solidification to form fine grained crystalline alloys based on
Al-Fe-V-Si, Al-Fe-Ce, and Al-Fe-Mo-V. While these alloys have shown promise in improving
use temperature, significant further improvement could be feasible by controlled
crystallization and consolidation of recently developed high crystallization temperature
glassy alloys (Tc=450C). However, conventional consolidation processes such as hot
pressing and hot isostatic processing are not amenable to simultaneous requirements
of full density, small grain size low cost. Recently, a quasi-isostatic high pressure
consolidation process developed by the firm enables consolidation at short times
(5-30 secs.) and at lower temperatures than hot isostatic processing while achieving
full density. Phase I will evaluate the feasibility of producing fully dense, ultrafine
grained aluminum alloys by controlled crystallization of a glassy aluminum Al-Si-Fe-Y
alloy which if thermally stable to high temperatures.
Phase I is expected to show that the goal of attaining 200F increases in use temperature
of aluminum alloy is feasible. The data generated in Phase I will enable Phase II
to focus on upscaled fabrication of large billets and will involve evaluation of
metal working to form sheets, forgings, and plates. Extensive mechanical testing
will also be carried out in Phase II.
metallic glass, crystallization, high temperature, alloy, rapid solidification

Project Title:

Low-Flow, Arc-Head Vacuum Welding

04.08-1933
900058
Low-Flow, Arc-Head Vacuum Welding

Abstract:

On-orbit welding for either assembly or repair of future spacestations and platforms
will require novel approaches to the design of the arc-type welding heads to ensure
that this very successful form of metal joining can be applied in the vacuum of space.
In particular, the clean welds accomplished using the Tungsten Inert Gas (TIG) and
plasma welding approaches make these common and fairly well understood techniques
highly desirable for space application. Although air contamination is not a problem
in space, existing commercially available TIG and plasma welding heads require large
inert gas flow rates (approx. l ;0 liters/min.) for arc stability. This gas consumption
requirement is unacceptable for a practical space-based welding technique. A novel
method of lowering this gas consumption will be developed by using a hollow cathode
in place of a solid Tungsten cathode electrode to reduce the inert gas flow requirement
to approx. 0.02 liters/min. for weld currents of hundreds of amperes.
Low-flow, Arc-Head Vacuum Welding would have application in future NASA and commercial
space-based fabrication. In addition, this vacuum welding concept could be a more
versatile and attractive technique than certain ground-based, electron=beam production
welding systems.
hollow cathode, low-flow, arc-head, vacuum welding

Project Title:

An Investigation into the Feasibility of GMA Welding in Space

04.08-2200
900804
An Investigation into the Feasibility of GMA Welding in Space

Abstract:

Construction and assembly of large structures will require use of various metal joining
processes. Welding is one of several methods under consideration for this purpose.
Gas Metal Arc (GMA) welding has advantages over other welding processes (i.e., laser,
election beam, and plasma arc welding) considered for use in space in that GMA welding
is more easily suited to manual and autonomous operation, requires less power to
operate, and equipment costs are considerably less. This effort will empirically
determine the feasibility of GMA welding in a vacuum and then project the influences
of weightlessness, temperature, and remoteness on the feasibility of using this process
in space. The successful development of the proposed GMA welding system will make
it a candidate for assembly and maintenance of large structures in space.
Applications include direct use by NASA contractors responsible for space station
assembly and maintenance. Indirectly, this development will reveal methods for improving
commercial weld processing on earth.
welding, automation, space, vacuum, assembly, construction, GMAW

Project Title:

Neural Networks for Welding Control

04.08-8877A
901072
Neural Networks for Welding Control

Abstract:

This project is developing methods to use artificial neural networks for modeling
and control of arc welding processes. Artificial neural networks will be compared
with more traditional models, such as those derived from the physics of heart conduction,
and techniques for combining the use of both in modeling and control will be explored.
Artificial neural networks are advantageous in that essentially no explicit model
derivation of the process is necessary. Rather, neural networks are trained with
real welding data from the process to be modeled, and they adapt themselves autonomously
to "learn" or capture the general process characteristics. It has been shown that
neural network models are generally numerically more accurate and usually faster
in execution than most of their traditional physically based counterparts. Typical
accuracy in predicting geometrical features of welds is on the order of 10% or better.
Physically based models, on the other hand, provide intuitive insight into the processes,
and they will be used here for guiding and checking the overall validity of the neural
network solutions.
This project is likely to result in increased productivity and improved process quality
of arc welding.
arc welding, process control, weld modeling, artificial neural networks

Project Title:

Feature Enhanced Ultrasonic Flaw Detection and Micro-structure Characterization Algorithms

04.09-1911A
901873
Feature Enhanced Ultrasonic Flaw Detection and Micro-structure Characterization Algorithms

Abstract:

for NDE Systems
In this project, some novel signal processing techniques for feature-enhanced, ultrasonic
NDE systems will be examined and implemented. The processing techniques have two
objectives:  to reduce the background noise in order to improve flaw visibility and
sizing and to obtain signal parameters that can be correlated to the microstructure
for characterization. An interactive software package for an Apple Mac II platform
adaptable to the NDE ultrasonic system at NASA will be developed and implemented.
For enhanced ultrasonic flaw detection, a split-spectrum processing followed by averaging,
median filtering, minimum detection, quadratic optimal detection, and generalized
order statistic filtering will be developed. Novel algorithms for microstructure
imaging and characterization such as temporal smoothing, dispersive velocity estimation,
correlation processing, homomorphic processing, power spectrum and moment estimation,
and linear predictive coding will be developed and implemented.
The system would allow cost-effective utilization of state-of-the-art signal processing
algorithms for improved flaw detection and microstructure characterization in a portable
ultrasonic nondestructive testing environment.
ultrasonic NDE, signal processing, flaw detection, microstructure characterization

Project Title:

Thermographic Stress Analysis and NDE via Focal Plane Array Detectors

04.09-8120
900334
Thermographic Stress Analysis and NDE via Focal Plane Array Detectors

Abstract:

This innovation will advance the state of the art and practical capabilities of thermographic
stress analysis (TSA) and nondestructive evaluation (NDE) to investigate and predict
the mechanical behaviors of models and real structures. A benchmarking method will
be established to optimize stress resolution and speed of imaging. A new TSA/NDE
system based on focal plane array detectors will be designed and analytically evaluated.
The objectives are to quantify the net capability of any existing or proposed TSA/NDE
instrument, estimate the expected improvement of the proposed system over current
ones, and create the preliminary design of an instrument with high stress resolution
and speed. The anticipated results of Phase I work will include a prototype benchmarking
instrument that will aid in determining the feasibility of the new TSA/NDE instrument.
The prototype of the new device will be made during Phase II, aiming for NASA applications
in basic material studies (monolithics and composites; wide range of temperatures),
and quantitative, stress-based NDE and life prediction of machines and structures.
The method will be capable of full-field, noncontacting analysis of objects loaded
sinusoidally or self-excited, such as engines.
The new TSA/NDE device will be commercialized by production and sale of standardized
or customized hardware and software and by contractual testing of materials, components,
machines and structures.
thermographic stress analysis, thermoelasticity, NDE, focal plane arrays

Project Title:

Liquid Crystal Polymers for CTE Matched PWBs

04.11-3200
902075
Liquid Crystal Polymers for CTE Matched PWBs

Abstract:

This project addresses the use of liquid crystal polymer (LCP) materials and processes
to fabricate laminated printed circuit boards (PCB) with the in-plane coefficient
of thermal expansion (CTE) matched to the ceramic chip carriers (6 to 7 ppm/oC) and
the out-of-plane CTE below 30 ppm/oC. This approach will solve the problem of thermal
fatigue related failures of solder joints enabling the implementation of surface
mount technology in space flight electronics. Also, this approach will enable the
use of reliable multilayer circuits by minimizing thermally induced stresses on plated,
through-hole vias. The result will be performance gains (weight and volume reductions
over 50 percent below current designs), clock speed and memory size increases, along
with reliability for long duration (up to 20 year) missions. In Phase I, a unique
film extrusion process followed by novel post processing techniques to tailor the
CTE of the LCP circuit layers will be used to  demonstrate that innovative materials
and processes can eliminate the problem of thermal fatigue in solder joints. In Phase
II, techniques will be developed for fabricating multilayer boards with LCPs. The
solder joint's performance and reliability advantages and commercial viability of
these new materials over the current state-of-the-art will be demonstrated.
Controlled CTE, multilayer PCBs will permit NASA's future space programs (such as
the Advanced Tracking and Data Relay Satellite System to utilize the increased speed,
smaller size, lighter weight, and larger memory offered by today's leadless ceramic
chip carriers and surface mount technology.
CTE matched boards, laminated printed circuit boards, liquid crystal polymers, solder
joint reliability, spacecraft electronics, electronics packaging

Project Title:

Automated NDE Scanner for Cracks

04.11-8166
900158
Automated NDE Scanner for Cracks

Abstract:

This project capitalizes on three emerging technologies by integrating a flexible
membrane as a highly efficient transducer, impressive scanning and imaging algorithms
found in medicine, and low-cost PC-based computers with a fast, digital signal processing
(DSP) board. The eventual machine shall be capable of supporting rapid testing of
ferrous and non-ferrous materials while on the assembly line with little operator
attention, thus reducing quality control costs directly at the factory as a type
of "go no go" detector. This will be possible in large part by the rugged and flexible
transducer harness which will be impervious to a harsh manufacturing environment,
the high quality of signal analysis afforded by tomography and the currently low
cost computers.
NDE of weldments, airframe integrity, mechanical bearing analysis, bone tissue diagnosis,
dental surgery, and economical seismic exploration will benefit greatly from a low-cost
expedient ultrasonic NDE analyzer.
NDE, ultrasonic, tomography, Gericke, PZDF

Project Title:

Conductive Paints Based on Soluble Conducting Polymers

04.11-9049
901998
Conductive Paints Based on Soluble Conducting Polymers

Abstract:

Recent unrelated work at the company has yielded a major breakthrough in conducting
polymer technology, with soluble, processible polymers with high solubility in organic
solvents, and homogeneous, reproducible thin films with conductivities as high as
1,000 S/cm. The present work seeks to further enhance conductivities of these polymers
based on trends identified in the prior work, and also to prepare and evaluate paints
by dispersing solutions of these elastomeric copolymers with conductive carbon black.
These copolymers will have anticipated superior conductivity, solubility, and processibility.
The work will also attempt to improve solubilizing, processing and coating techniques.
The design of the targeted new copolymers includes consideration of improved elastomericity
for better cryogenic application and environmental stability via exclusion of reactive
substituents. Besides the advantages of weight, processibility, one-component nature,
and stability , the proposed paints will be more conductive than currently available
paints based on non-conductive binders
Light-weight, processible and stable conductive coatings can be utilized in EMI shielding,
IR emissivity and radar signature reduction, and electrochromic displays.
conductive, paint, soluble, conducting, polymer, cryogenic

Project Title:

Use of Honeycomb Technology to Save Weight in Composite Flexible Blanket Insulation

04.12-5367
901486
Use of Honeycomb Technology to Save Weight in Composite Flexible Blanket Insulation

Abstract:

Space Shuttle flights have demonstrated the value of flexible ceramic blankets such
as Advanced Flexible Reusable Surface Insulation (AFRSI) for reentry thermal protection
on areas exposed to moderate heating rates. Other ceramic blankets are being developed
for future spacecraft such as the NASP, Shuttle-C, and Aeroassist Orbital Transfer
Vehicles. Pitts and Kourtides (1989) describe a hybrid insulation combining ceramic
blankets and Multi-Layer Insulations (MLI) which could reduce blanket weight by 500
g./sq.m. The advantage is realized because MLI's are approximately 100 times less
conductive than ceramic blankets. This project will investigate further improvements
in MLI's made possible by substituting honeycomb separators for the scrim or crinkled
Kapton currently used in MLI's. The flexible honeycomb layers, which may be produced
from polymeric or ceramic materials, are expected to be more durable than the crinkled
Kapton and significantly lighter in weight than scrim. The additional wight saved
through the use of honeycomb could exceed 700 g./sq.m. The work will include thermal
conductivity measurements of samples at temperatures of 300o to 1300oK and pressures
of 0.01, 0.1 and 1.0 atmosphere pressure. The data will be incorporated in a computer
model to predict benefits to NASA missions.
High temperature insulation developed for spacecraft thermal protection systems will
spin-off insulations for commercial aircraft, ovens, cryogenic systems, and other
industrial applications.
multilayer insulation, thermal protection systems

Project Title:

Six Degree of Freedom Active Vibration Damping for Space Applications

04.13-2407
900529
Six Degree of Freedom Active Vibration Damping for Space Applications

Abstract:

This project deals with vibration damping in space applications. The company has
spent two years investigating and then simulating control of a high-speed, high-precision,
six-degree-of-freedom motion stage based on a six-legged, parallel-link manipulator.
This system exploits six magnetostrictive actuators, one in series with each conventional
leg actuator. This allows the conventional actuators to provide six-degree-of-freedom
positioning while the six magnetostrictive actuators (which elongate under the freedom,
high-frequency vibration isolation. Magnetostrictive elements are extremely light
and can exert large forces at high frequencies. The six-legged, parallel-link mechanism,
called a Stewart Platform, provides a means to convert this one dimensional displacement
into six-dimensional, high-frequency, high-precision motion. In space structures,
the vibrational forces will include flexing and twisting, and we believe that six
axis counter motion is essential to implementing high performance active vibrator
 isolation and damping. The system being investigated will meet this requirement.
This system would apply to engine quieting, camera stabilization, precision microscopy,
and six axis machining.
parallel link manipulator, vibration isolation, feedforward control, Steward Platform,
six axis manipulator.

Project Title:

Quick Look Modal Testing of Flexible Structures

04.14-2733
900163
Quick Look Modal Testing of Flexible Structures

Abstract:

An innovative modal test analysis technique for successful ground testing of large
precision space structures will be investigated. In particular, traditional approaches
to modal testing are hampered by the overwhelming amount of data which must be acquired,
stored and analyzed for these large flexible structures, which reflects directly
on testing costs and time. The application of data compression principles to modal
analysis is proposed as a method of providing a cost-effective, quick look at the
test data. This is accomplished by a combined automated zooming in on the band-widths
of interest, and efficient manipulation of the compressed information for the eventual
visualization of the modal data. The speed and accuracy of the proposed quick look
method will be compared to standard modal testing algorithm such as ERA, ITD and
the polyreference method.
This method is potentially faster than existing research and commercial packages
and would be applicable to all areas of modal testing (auto industry, spacecraft,
computer industry, etc.)
rule based data retrieval, data compression, mode shape

Project Title:

Development and Fabrication of Multi-Inlet Tubular Joint Structures for Spacecraft

04.14-5325A
900721
Development and Fabrication of Multi-Inlet Tubular Joint Structures for Spacecraft

Abstract:

Application
There exists a need for integrally woven composite joint structures in the aerospace
community. Joining technology has not kept pace with the improvements made to current
and projected spacecraft accommodating the increasingly harsh environments that spacecraft
are subjected to during flight. This effort will focus on the development of the
technology necessary to integrally weave complex multi-inlet joint structures.  Graphite
fiber tows will be used to fabricate the woven fiber preform, and the resulting composite
system will be infiltrated with molten metal to form a metal matrix composite. Development
of this type of joint will offer the improved mechanical properties of the integrally
woven preform and the enhanced environmental stability of the metal matrix. The resulting
joint technology will allow spacecraft manufacturers to utilize a whole new family
of composite joint systems.
New composite joint technology will play a key role in space structure assembly (both
ground-based and in space) and in next generation supersonic aircraft as well. These
joints may be applicable to many high temperature applications including future hypersonic
transports such as NASP and HSCT.
Integrally woven, multi-inlet joint, preform, space structures, composites

Project Title:

Magnetic Energy Absorber for Docking Impact Attenuation

04.14-7351
900840
Magnetic Energy Absorber for Docking Impact Attenuation

Abstract:

Magnetic, eddy-current devices based on rare-earth magnets are very attractive as
passive absorbers of impact energy for spacecraft. Their advantages include highly
predictable behavior, all-metal construction, insensitivity to temperature, high
force/velocity ration in a light, compact package, ruggedness, simplicity, reliability,
and ease of force profiling. A single unit capable of dissipating the kinetic energy
of a typical Orbitor-Station docking could weigh less than 20 Kg. A long stroke (order
of 1 M) is practical and could be used to keep the peak impact force quite small.
This effort will investigate the feasibility of a magnetic energy absorber as a docking
impact attenuator for Space Station Freedom. A dynamically scaled demonstrator device
will be designed, fabricated, and tested within Phase I. Correlation of analytical
design predictions and test results will be used to evaluate scalability of the design
to the required size.
Magnetic energy absorbers (dashpots) could be used to advantage in a number of current
applications where a viscous damper must function with high reliability in a hostile
environment or over a wide temperature range. Examples are seismic pipe snubbers
in nuclear plants or tuned-mass vibration dampers for low-frequency structures such
as aircraft and spacecraft.
impact attenuator, dashpot, damper, docking, magnetic

Project Title:

Epitaxial Growth of Semiconductors on High-Tc Superconductor Crystals

04.15-0046
900526
Epitaxial Growth of Semiconductors on High-Tc Superconductor Crystals

Abstract:

This project in investigating the epitaxial growth of semiconductors (Si and GaAs)
on single crystal, high temperature superconductors. These materials will lead to
the monolithic integration of high temperature superconducting devices and electronic/optoelectronic
semiconductor devices. Epitaxial semiconductor/high-Tc-superconductor materials will
also lead to the invention of new devices involving the interplay of the as yet unknown
superconducting mechanism and semiconductor physics. The development will involve:
 development of a method for substrate preparation, the determination of the substrate
surface behavior in ultra-high-vacuum at temperatures up to the film growth temperatures;
the determination of the optimum parameters for growth of each semiconductor, and
the characterization of the semiconductor/high-Tc-superconductor materials to determine
structural, electrical, magnetic, and optical properties. Phase II will study the
use of epitaxial semiconductor/high-Tc-superconductor materials for monolithic integrated
circuit sensors, superconducting mixers for millimeter and far-infrared receivers,
and semiconductor circuits for high-speed, on-chip signal processing.
Applications would occur in millimeter/far-infrared receivers with wide bandwidth
and low noise, focal plane array receivers with on-chip signal processing and monolithic
integration of high-speed superconducting electronics and semiconducting electronics
and optoelectronics.
superconductor, semiconductor, electronics, epitaxy, film, monolithic, circuit, mixer

Project Title:

Large Area, High-Temperature Superconducting Thin Films

04.15-6700
900927
Large Area, High-Temperature Superconducting Thin Films

Abstract:

The high-temperature superconducting films now deposited in situ are large enough
for research purposes and for production of a limited number of devices. But most
practical devices and circuits will require high-quality films o large substrates.
This project will develop a process for depositing high-quality films of YBa2Cu3O7-d,
with uniform thickness and uniform electrical properties, in technologically useful
sizes - that is, on substrates 2 to 4 inches in diameter. Tools for measuring the
properties of the large films locally as well as in their entirety will also be developed.
The availability of large films and tools for characterizing them will accelerate
the commercialization of high-temperature electronics.
There are many commercial applications of high-temperature superconductors such as
delay lines and chip-to-chip interconnects that require large areas of superconducting
film patterned so as to provide the desired circuit characteristics.
superconductors, high temperature superconductors, large area, thin films

Project Title:

Buffer Layers on Low Substrates for High Temperature Superconducting Thin Films

04.15-7646A
901324
Buffer Layers on Low Substrates for High Temperature Superconducting Thin Films

Abstract:

The objective of this project is to develop epitaxial buffer layers grown by chemical
vapor deposition (CVD) that will provide both a diffusion/reaction barrier and a
transition in crystal structure and lattice parameter between a low-loss, single-crystal
substrate and an epitaxial, single-crystal, high-temperature superconducting film.
Phase I will establish proof of concept via homoepitaxy.;  For example, MgO films
will be grown on single crystal MgO substrates and LaA103 films will be grown on
single crystal LaA103 substrates. The films will be evaluated for crystal quality,
surface smoothness, and uniformity, and process conditions will be adjusted to optimize
film properties. In Phase II the process will be extended to heteroepitaxy, with
the goal of providing epitaxial buffer layers for superconducting films on substrates
such as single crystal A12O3 (sapphire) that are highly desirable for microwave applications.
A process that can successfully epitaxial buffer layers on sapphire will provide
significant benefit for the manufacture of superconducting films and devices for
microwave applications.
CVD, epitaxy, superconductor, thallium, film, buffer layer, microwave, losses

Project Title:

Field Emission Enhancement and Confinement from Superconductive Surfaces

04.15-8623
900065
Field Emission Enhancement and Confinement from Superconductive Surfaces

Abstract:

This project studies the feasibility of using a superconductive surface as the source
of electrons for electron beam diode applications. Ceramic based materials such as
YBa2Cu3O6+x will be tested. The material will be deposited as a coating on a metal
electrode. The same material will be also tested in solid form. This work will correlate
the field emission characteristics of the superconductive surface with the field
emission formulations of Fowler-Nordheim and Richardson-Dushman. Feasibility of using
superconductive materials as electron sources for beam diodes will be determined
by demonstrating coating integrity and superconductive material electron emission
under DC and high voltage pulsed regimes. If this concept is feasible current densities
of more than 100 A/cm2 will be demonstrated during the Phase I program.
Some of the anticipated benefits include:  high current density electron beam source
for FEL, modulated-electron diode with the emission surface turned on and off by
a modulating magnetic field, accelerator resonant cavities with controlled or no
field emission, and microwave oscillators in which the oscillating magnetic field
controls the electron emission source.
superconductor, field emission, electron beam

Project Title:

An Innovative Technique to Produce High Jc, High-Strength HTS Wire Using Newly Discovered

04.15-9023A
901929
An Innovative Technique to Produce High Jc, High-Strength HTS Wire Using Newly Discovered

Abstract:

Processes and Materials
The company has developed a concept to produce functional super-conducting wire using
the heretofore unsuccessful 'powder in tube' process, dynamic compaction of the melt
process phase of SHS material generation, and high pressure operation of the resultant
aligned crystalline structure. The pre-reaction SHS powders will be placed in a silver
tube. These powders will then be ignited using normal SHS mixtures and processes.
 As the flame progresses down the tube creating a melt-phase liquid, the tube will
be swaged down to dynamically compact the melt. This will force the crystals to lay
down along their long axes in the tube. Upon cooling, the silver tube will contract
a greater amount than the ceramic superconductor putting the ceramic under pressure
to improve the Tc and Jc. The company will use its BISCCO-Pb powder which as a Tc
onset of 117K.
Applications would be in high power magnets, antennas, power and data conductors,
and sensors

Project Title:

High-Tc Superconducting Composites for Interconnects to Cryogenic Equipment

04.15-9450
900912
High-Tc Superconducting Composites for Interconnects to Cryogenic Equipment

Abstract:

A vacuum deposition process that promotes crystallographic orientation and high critical
currents in YBa2Cu3O7-x films deposited on ceramic substrates will be developed as
a means of fabricating flexible electrical interconnects to cryogenic equipment in
the space environment. The interconnects will comprise a thin film of high-Jc YBa2Cu3O7-x
deposited onto flexible ceramic tapes and filaments, a buffer layer, a vacuum deposited
oxide overlayer, and a low out-gassing polymer encapsulant. Methods for reducing
both conductive and radiant heat transfer are incorporated into the design. The interconnects
would have significantly lower thermal conductivity, no I2R losses (for DC applications),
and would be of equivalent or lower wight than conventional metal interconnects.
The low thermal conductivity will minimize cryogen (primary liquid helium) loss and
significantly increase the mission life of sensors and other equipment requiring
cryogenic cooling. The principal technical objective of the Phase I program is to
demonstrate the deposition of high-Jc YBa2Cu3O7-x (Jc-106 A/cm2 at 77 K) on flexible
tapes and filaments with an Ic of 20 A at 77 K.
Spaceborne applications include optical sensors and cryogenic equipment (e.g., superconducting
magnets) in scientific and military satellites with long mission life requirements.
Applications also extend to interconnects between cryogenically cooled electronic
packages were I2R heating and thermal conduction must be minimized.
superconductors, interconnects, YBa2Cu3O7-x, thermal conductivity, vacuum coating

Project Title:

Recovery of Oxygen from Lunar Soils in a Plasma Reactor

04.16-3200
902076
Recovery of Oxygen from Lunar Soils in a Plasma Reactor

Abstract:

The specific focus of this project is a plasma process for the recovery of oxygen
at high yield from minimally beneficiated lunar soils, where the soil is dissociated
into its elements in a plasma arc and the oxygen is recovered by quenching the product
mix. The objective of the Phase I program is to determine the feasibility of oxygen
recovery from lunar soils in a plasma reactor without the addition of chemicals.
Theoretical and experimental studies are planned. The theoretical part of the program
will estimate the temperature needed to ensure that most of the ore is dissociated
into atoms, and the heat transfer rate required to quench the reaction of cooling
the product stream. These results will then provide the basis for evaluating the
findings of the experimental tests to be conducted in a laboratory-scale plasma reactor.
Cost estimate for a full-scale facility will be estimated.
This process can be adapted to developing an extremely clean and efficient technique
for handling terrestrial waste. The process has the potential of breaking down and
separating the most objectionable compounds in terrestrial waste.
plasma, oxygen recovery, quenching, lunar soils, ilmenite

Project Title:

Novel Approach to the Electrolysis of Oxides

04.16-3260
900332
Novel Approach to the Electrolysis of Oxides

Abstract:

Electrolysis of lunar oxides dissolved in a molten electrolyte is a promising approach
to produce oxygen on the moon for propulsion and sustaining human life. Molten fluorides
have been considered a s electrolytes in the past, because of their relatively low
melting point and their high specific electrical conductivity. A properly selected
all-oxide electrolyte may have similar beneficial properties and additional advantages
in critical areas of the electrochemical process. This project, thus, involves the
study of oxide melts and their application to the electrolysis of oxide mixtures
as they occur in readily available lunar resources.
The results of the study are expected to be of direct pertinence also to the development
of advanced terrestrial electrolytic processes, e.g., to produce aluminum metal with
greater energy efficiency and without the emission of carbon dioxide.
lunar electrolysis, oxygen production, molten electrolytes, oxides

Project Title:

Human-Machine Interaction in Human Assisted Robotic Systems

05.01-0970
900960
Human-Machine Interaction in Human Assisted Robotic Systems

Abstract:

This project introduces a new class of robot manipulators called "extenders."  Extenders
are worn by humans and increase human mechanical ability while the human's intellect
serves as the central intelligent control system for manipulating the extender. The
human body, in physical contact with the extender, exchanges power and information
signals with the extender. This project's objective is to develop ground rules for
the control of robotic systems worn by humans through the design, construction, and
control of a simple experimental extender. This knowledge will be the basis for the
design and construction of a multi-degree-of-freedom extender in Phase II.
The technique is applicable in areas where human power needs to be amplified but
still retain precise operator control such as cargo handling or construction. An
example application might be a human power amplified forklift.
extenders, human power amplifiers

Project Title:

Analysis of the Human Musculoskeletal System for Teleoperator System Design

05.02-0649
901331
Analysis of the Human Musculoskeletal System for Teleoperator System Design

Abstract:

Teleoperators are key components of future space exploration missions. As the use
of teleoperators and the length of time people operate them increases, it has become
necessary to evaluate the physiological and ergonomic parameters of the system. This
project addresses this need by modeling the human musculoskeletal (m-s) system. The
motion of the limbs and the muscle and joint reaction forces required to produce
the teleoperator motion and overcome its feedback forces are included. The model
will be used to establish and verify representations for physiological performance
degradation due to pain and exhaustion and to suggest optimal positions to extend
the operator's performance. Phase I of this project will be concerned with the development
of a general modeling procedure for the human m-s system and assess its application
in the evaluation of human performance of teleoperators.
This model would provide teleoperators with better ergonomic design and lower cost
of design, more effective designs of the work place for manual labor jobs, and improved
artificial joint designs.
biomechanics, musculoskeletal systems, robotics, teleoperators, telerobotics

Project Title:

An Integrated Micro-gyroscope

05.03-0540A
901857
An Integrated Micro-gyroscope

Abstract:

Micro-electronic fabrication technologies have recently been applied to produce novel
micro-mechanical devises such as motors, sensors, and actuators. Their small size
and easy integration with micro-electronics invite innovative research, but thus
far few useful application concepts have been developed. One device with widespread
application would be an electrically suspended micro-gyroscope. The motor, sensor,
suspension, and control and interface electronics could be packaged on a single chip.
The devices could be produced for low cost in large quantities and see widespread
use in integrated navigation and control