Oscillating P-residuals
 

Hello :)
currently I am investigating a rotating tempered cylinder.
First I tried the incompressible and steady case and determined the u+ and y+ values. Now that I am satisfied with the results so far and I wanted to implement the heat exchange into the simulation.
But with the calculations, both with buyantPimpleFoam and buyantSimpleFoam, oscillating P-residuals always occur. I have already changed the fv-scheme (Euler, CrankNicolson 0.5, backward) several times and tried to use more diffuse div-scheme.
Because I have never calculated compressibly, my knowledge is very limited here.
Does anyone have any experience with this kind of problem?

I hope that the information in the appendix is sufficient to help me here and find my bug.

This Simulation was calculated with:
buyantPimpleFoam and gravity

Best regards
Kevin