hello there.
I have followed the tutorial of Incompressible CFD simulation over a car in external flow section of SimScale. I am unable to get results as the values of Cd and Cl starts diverging after several iterations. I have attempted simulation for two values of stream velocities, 1 m/s and 0.5 m/s. Also for stream velocity of 0.5 m/s the values diverge so much that it causes to fail the simulation itself. This sudden diverge of values is difficult to explain. Please guide me. Thanking you in advance.
Hi Shashwat, the CAD model for the vehicle tutorial was recently updated, after receiving some clean up. So my suggestion would be to import the new model using the button at the beginning of the tutorial here:
Also keep in mind to check this pages when divergence occurs:
Hi Fillia, I have again gone through the tutorial guide, but I guess there wasn’t any change. I tried identifying the divergent point and then checked for the mesh quality, but there wasn’t poor mesh quality at the defined point. The meshing log does shows several parameters above maximum limit, I don’t know if that would cause such a divergent. The possible way there could be now is that I perform very fine mesh but that would take too much computational time and so I want it to be the last option. I would be thankful if you could again look at the model and help me pinpoint the problem based on your experience. Hope to hear from you soon,
Hello again, I used your geometry as a reference. Everything was same, but just region refinement for larger box was not active, though I had applied it. I don’t know what could be the reason. On redefining it and regenerating the mesh, the simulation worked and the values are convergent. Basically, it was the mesh that needed a look. Thank you very much for your time and help.
