CFD at Mach 0.85

Using SimScale Fluid Flow / CFD
1

Hello,

I am currently trying to determine the drag coefficient (Cd) of our rocket booster at Max Q, which occurs at approximately 290 m/s. To do this, I followed the Compressible Flow simulation tutorial provided by SimScale.

However, my simulations keep failing. I have attempted multiple runs while adjusting the boundary conditions and mesh refinements, but I continue to receive the same error each time.

In the simulation log, several faces are referenced in the error message. When I click on these faces, nothing is highlighted in the geometry viewer, so I am unable to identify which surfaces are causing the issue.

At this point, I’m not sure whether the problem is related to my simulation setup or if there may be an issue with the CAD model itself.

Any guidance on how to diagnose or resolve this would be greatly appreciated.

>> Mesh

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image690×1604 148 KB

2

Hi,

I understand your concern. Unfortunately, our compressible solver is not designed for high-speed flows (Ma > 0.6), so this issue is likely due to the solver itself rather than the setup or CAD geometry.

For reference, the two external compressible flow simulations show maximum velocities of 165.1 m/s (Compressible Flow Around a Wing) and 72.65 m/s (Compressible CFD Simulation on a Golf Ball).

Bryan