Langley Research Center Turbulence Modeling Resource

2D Planar Shear Verification Case - Intro Page

The purpose here is to provide a large sequence of nested grids of the same family, along with results from existing CFD codes that employ specific forms of particular turbulence models, in order to help programmers verify their implementations of these same models. On a given grid, there may be differences between the results from different codes, but presumably as the grid is refined the results should approach the same answer (if the flow conditions and boundary conditions are the same). With verification, the purpose is not to establish the "goodness" of a model compared to experiment, but rather to establish that a model has been implemented correctly, as intended according to the equations and boundary conditions. (It is through validation that a model's "goodness" is established.) The purpose here is primarily verification.

The planar shear case focuses on the development of the free shear layer following the passing of two different streams over a thin plate. The smaller inner stream has Mach number near M=0.5, whereas the outer larger stream has a Mach number near M=0.25. This can also be considered as a planar co-flowing jet (see Rajaratnam, N., Developments in Water Science: Turbulent Jets, Elsevier Scientific Publishing Company, New York, 1976). The Reynolds number is Re = 50,000 based on length "1" of the grid. The computational domain extends from -10 < x < 200, and 0 < y < 100. The separating plate extends from -10 < x < 0 at y=0.5. Both the lower and upper boundaries are taken to be symmetry planes. The following plots show the layout of this case, along with the boundary conditions. (Note that particular variations of the BCs at the inflow, top wall, and outflow may also work and yield similar results for this problem.)

• GRIDS
• SA EXPECTED RESULTS
• SST-V EXPECTED RESULTS