NASA SBIR 00-1 SOLICITATION

FORM 9B - PROJECT SUMMARY


PROPOSAL NUMBER 00-1 02.02-8624 (Chron: 001377 )
PROJECT TITLE
Turbulence Framework for Jet Noise Prediction and Reduction



TECHNICAL ABSTRACT (LIMIT 200 WORDS)
The innovation proposed is the construction of a unified nonlinear turbulence model for use in jet noise studies that will operate in an invariant manner (fixed coefficients/correction terms), and will provide reliable mean flow and anisotropic stresses predictions for a broad range of jet conditions. Model construction will be based on extensions to an operational explicit algebraic stress model (EASM) framework that includes anisotropic dissipation, compressibility, and vortex-stretching extensions, and is supplemented by additional scalar fluctuation and dissipation rate equations used to locally evaluate turbulent Prandtl and Schmidt numbers. CRAFT Tech will be supported by Seiner and coworkers at U. Miss who will obtain 3D PIV data for Mach .85 and 1.5 cold and hot jets to support model calibration. Acoustics data will also be obtained in this effort, and simulations performed via coupling the CFD solution with an acoustics analogy noise code (such as MGB) will be compared with this data. In Phase II, the model will be extended to more complex 3D propulsive jets that include varied mixing enhancement devices. In addition, propulsive interfacing and aerodynamic interactions will be addressed.



POTENTIAL COMMERCIAL APPLICATIONS
The primary commercial application of this advanced turbulence framework relates directly to the support work and software licensing we now perform for prime contractors (Lockheed, Pratt, ) relevant to the design assessment of mixing enhancement devices for IR signature reduction. We are presently supporting work related to the C-130, the F-18 and the F-22 where we are performing design assessment simulations and training personnel in the operation of a specialized aircraft/rotorcraft unstructured grid end-to-end code. Inclusion of this advanced turbulence framework into this code will greatly enhance our simulation capabilities and will permit us to also support commercial aircraft efforts related to assessment of noise reduction concepts via coupling our solutions with noise codes such as MGB. Other opportunities reside in the turbomachinery community where RANS turbulence modeling with advanced heat transfer and nonlinear strain capabilities is presently deficient.



NAME AND ADDRESS OF PRINCIPAL INVESTIGATOR (Name, Organization Name, Mail Address, City/State/Zip)
Donald C. Kenzakowski, Jr.
Combustion Research and Flow Technology, Inc.
174 North Main Street, P.O. Box 1150
Dublin , PA   18917 - 2108



NAME AND ADDRESS OF OFFEROR (Firm Name, Mail Address, City/State/Zip)
Combustion Research and Flow Technology,
174 North Main Street, P.O. Box 1150
Dublin , PA   18917 - 2108