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Axisymmetric Transonic Bump Validation Case

SST-RCm Model Results
 

Link to SST-RCm equations

SST-RCm - surface pressure coefficient SST-RCm - surface skin friction coefficient

SST-RCm - u velocites SST-RCm - turbulent shear stresses

Previously on this page the results were reported as SST-RC solutions, but more properly they should be referred to as SST-RCm. Essentially no difference is expected.

Note that thorough grid studies were not performed for validation cases such as this one. Some effort was made to ensure reasonable grid resolutions, but there may still be small noticeable discretization errors. Therefore, these validation results shown should be considered representative, but not "truth."

The plots compare the SST-RCm results from CFL3D and FUN3D with experimental data. The CFD codes predict the flow separation to occur near x/c = 0.645 and the reattachment near x/c = 1.17 (in experiment these were 0.7 and 1.1, respectively). Both codes used freestream turbulence intensity=0.0089% and freestream turbulent viscosity (relative to laminar)=0.009 (additional details can be found in the CFL3D User's Manual, Appendix H). Please read note 5 on Notes on running CFD page. These results are from the second-finest grid (721x321). Both codes yield nearly identical results, and these are also very close to results for the SSTm and SST-2003m models. The data files from CFL3D are given here: axibump_cfl3d_cp_sstrc.dat, axibump_cfl3d_cf_sstrc.dat, axibump_cfl3d_u_sstrc.dat, axibump_cfl3d_uv_sstrc.dat. (Note: the profiles have been interpolated using Tecplot software onto pre-set points, that may or may not correspond to the actual grid points or grid cells used in the computation.) A typical CFL3D input file is: axibump_cfl3d_typical_sstrc.inp. A typical FUN3D input file is: fun3d.nml_typical_sstrc_2.

As for other two-equation model cases posted on the TMR website, the - (2/3) \rho k \delta_{ij} \partial u_i / \partial x_j term in the turbulence production was ignored (often the default for codes whose predominant applications are low-speed or transonic cases; see notes 4 and 7 on the Notes on Running the Cases with CFD page). This approximation makes only a very small difference in results for this case, as demonstrated on the BSLm model results page.

Note that this model is currently assigned MRR Level 2 for the purposes of this website. This is because the model has not yet been applied to a verification case, including complete grid convergence study. The results on this page are therefore not necessarily reliable until such a verification can be completed.

In this case CFL3D was run on a version of the 3-D grid that was centered around the x-z plane, rather than on the posted grid that has one plane aligned with the x-z plane (1 deg. still separated the two planes).
 
 

Jump to: SA ResultsSA-RC ResultsSSTm ResultsSST-2003m ResultsBSLm ResultsSSG/LRR-RSM-w2012 ResultsWilcox2006-klim-m ResultsK-kL-MEAH2015m Results

Return to: Axisymmetric Transonic Bump Validation Intro Page

Return to: Turbulence Modeling Resource Home Page


 
 


Recent significant updates:
01/28/2019 - mentioned that CFL3D version of grid is centered about x-z plane

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Last Updated: 03/06/2025