NASA SBIR 2008 Solicitation


PROPOSAL NUMBER: 08-1 A2.03-9755
SUBTOPIC TITLE: Aero-Acoustics
PROPOSAL TITLE: Hybrid Element Method for Mid-Frequency Vibroacoustic Analysis

SMALL BUSINESS CONCERN (Firm Name, Mail Address, City/State/Zip, Phone)
Comet Technology Corporation
3830 Packard, Suite 110
Ann Arbor, MI 48108 - 2051
(734) 973-1600

PRINCIPAL INVESTIGATOR/PROJECT MANAGER (Name, E-mail, Mail Address, City/State/Zip, Phone)
S T Raveendra
3830 Packard, Suite 110
Ann Arbor, MI 48108 - 2051
(734) 973-1600

Expected Technology Readiness Level (TRL) upon completion of contract: 4 to 5

TECHNICAL ABSTRACT (Limit 2000 characters, approximately 200 words)
In many situations, aerospace structures are subjected to a wide frequency spectrum of mechanical and/or acoustic excitations and therefore, there is a need for the development of numerical modeling techniques that are applicable for the resolution of dynamic response of complex systems spanning the entire frequency spectrum. However, the dynamic behavior of these structures at different frequency range is governed by different phenomena and as a result, a single numerical solution procedure is not suitable for the resolution of the entire frequency spectrum. Thus, on the basis of the numerical modeling techniques, the frequency spectrum is typically divided into three regions; low frequency region, mid-frequency region and high frequency region. The low frequency region is the frequency range where the characteristic dimensions of all component members of a vibroacoustic system are short with respect to wavelengths and these members are also referred to as 'short' members. On the other hand, in the high frequency region, the characteristic dimensions of all component members are long with respect to wavelengths and these members are referred to as 'long' members. There exists a broad mid frequency region in which not only some components are long and others are short with respect to wavelengths The proposal is directed towards the development of an innovative hybrid element method by coupling deterministic, transition and statistical Finite Element Methods to yield a solution system that is applicable for the solution of full frequency spectrum vibroacoustic prediction of nonuniform aerospace structures including metallic/composite configurations, accurately and efficiently.

POTENTIAL NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The development of space vehicles and space stations requires the prediction of vibration levels to asses the fatigue life of critical components and noise levels to assess the comfort and functionality levels of crew members. The software product developed as part of the proposed project will enable NASA to effectively evaluate and apply noise and vibration control procedures spanning the entire frequency spectrum. It will also substantially reduce the effort involved in the design of products since the proposed development is based on finite element method that is already used extensively for low frequency noise and vibration analysis. Since low frequency (FEM), mid frequency (HEM) and high frequency (EFEM) analyses can be performed using mostly the same database, the modeling effort associated will be substantially reduced. The software will also enhance NASA's ability to evaluate the acoustic environment and resulting vibration in the payload bay of launch vehicle, diffuse sound field excitation on payloads during rocket launch and ground qualification, and structural integrity of airframe. Manufacturers of aircraft engines and components will also find the software useful for analysis and design.

POTENTIAL NON-NASA COMMERCIAL APPLICATIONS (Limit 1500 characters, approximately 150 words)
The proposed development will extend and enhance the computational modeling capabilities in many industries such as automotive, naval, heavy equipment and consumer products. Customers equate quality of a product with the sound the product makes. As a result of elevated demand for quieter products from customers together with the increased government regulations, manufactures of products with noise problem in all industries are searching for effective ways to make products with improved noise characteristics. For example, in automotive industry, the increased use of multi-media and telemetric devices demands quieter vehicle interiors and the manufactures and suppliers of interior products not only need to consider functionality, but also the noise control capability of the products. Consequently, there is increasing demand for tools based on computer simulation that can be used to guide design at the early design stage. Further, the software can be adapted to evaluate and improve radiated noise from engines, exhaust, tires, etc. It can be used to evaluate and improve consumer products such as compressors, air conditioners, hairdryers, vacuum cleaners, and washing machines.

NASA's technology taxonomy has been developed by the SBIR-STTR program to disseminate awareness of proposed and awarded R/R&D in the agency. It is a listing of over 100 technologies, sorted into broad categories, of interest to NASA.

Launch and Flight Vehicle
Structural Modeling and Tools

Form Generated on 11-24-08 11:56