Look at the “incompressible 2” run only. This weird spike only happens in the 1 degree AOA trial of the model and all other angles demonstrate convergence. My mesh is fully resolved and presents no issue in any of the trials. Wake separation shouldn’t be an issue at 1 degree. The lift coefficient is negative for some reason all the other trials make sense. Wondering why this is. Ran this thing through 8,000 iterations just to make sure. It appears to have converged to the incorrect value. Keep in mind the flow is in the -z direction.
Thanks for providing a detailed description of the issue and including your project link. I can’t access the project directly to view the setup (it seems to not be shared with support), but based on your explanation, the behavior you’re seeing with the negative lift coefficient could be the sign of a settings mismatch in your result controls.
When the flow is in the negative z-direction, it’s crucial to ensure that the lift and drag vectors in your “Forces and moments” result control item are correctly aligned with your geometry’s orientation. A negative lift coefficient in this scenario almost always points to the lift direction vector being defined opposite to what you’d expect.
Please check your “Forces and moments” settings under Result Controls and verify the following:
Lift direction: Ensure this vector points in the direction you consider to be positive lift.
Drag direction: This should be aligned with the direction of flow.
You can find more detailed information on how to configure these settings in the SimScale documentation on Result Control.
Let us know if that resolves the issue or if you already managed to resolve the error, as it’s been a while since you posted!
