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Accession Number N14-0002507
Title Modeling of Turbulent Free Shear Flows.
Publication Date Aug 2013
Media Count 38p
Personal Author D. A. Yoder J. R. DeBonis N. J. Georgiadis
Abstract The modeling of turbulent free shear flows is crucial to the simulation of many aerospace applications, yet often receives less attention than the modeling of wall boundary layers. Thus, while turbulence model development in general has proceeded very slowly in the past twenty years, progress for free shear flows has been even more so. This paper highlights some of the fundamental issues in modeling free shear flows for propulsion applications, presents a review of past modeling efforts, and identifies areas where further research is needed. Among the topics discussed are differences between planar and axisymmetric flows, development versus self-similar regions, the effect of compressibility and the evolution of compressibility corrections, the effect of temperature on jets, and the significance of turbulent Prandtl and Schmidt numbers for reacting shear flows. Large eddy simulation greatly reduces the amount of empiricism in the physical modeling, but is sensitive to a number of numerical issues. This paper includes an overview of the importance of numerical scheme, mesh resolution, boundary treatment, sub-grid modeling, and filtering in conducting a successful simulation.
Keywords Aerospace engineering
Axisymmetric flow
Computational aeroacoustics
Computational fluid dynamics
Free flow
Jet aircraft noise
Large eddy simulation
Mixing layers(Fluids)
Navier-stokes equation
Prandtl number
Reynolds averaging
Schmidt number
Shear flow
Turbulence models
Turbulent flow

Source Agency National Aeronautics and Space Administration
NTIS Subject Category 46B - Fluid Mechanics
51A - Aerodynamics
Corporate Author National Aeronautics and Space Administration, Cleveland, OH. NASA John H. Glenn Research Center at Lewis Field.
Document Type Technical report
Title Note N/A
NTIS Issue Number 1421
Contract Number N/A

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