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Axisymmetric Subsonic Jet Validation Case
SA Model Results
Link to SA equations
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 shown compare the SA results from two independent
CFD codes: CFL3D and WIND, along with experimental data.
CFL3D used freestream value of the SA turbulence field variable (relative to laminar)=3,
while WIND used a value of 5.
Please read note 5 on Notes on running CFD page.
These results are from the second-finest grid (97x97; 61x97; 257x225).
Both codes gave nearly identical results to each other.
Notes: (1) For this particular case the SA model does not converge readily to a steady-state result
when using either of these two codes on this (or on the finer) grid. However, when run time-accurately, the
solution settles down and becomes reasonably steady (quasi-steady);
(2) For axisymmetric cases such as this (with singular axis of symmetry), it is important to
solve the turbulence dissipation terms in a strong conservation form;
(3) These are compressible code results run on a subsonic case. There may be a small influence of compressibility.
No specific turbulence model compressibility corrections have been employed.
The data file from WIND is given here:
jetsubsonic_wind_sa.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 WIND input file is:
jetsubsonic_wind_typical_sa.inp.
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Responsible NASA Official:
Ethan Vogel
Page Curator:
Clark Pederson
Last Updated: 08/28/2020