[MagicCFD]

Hello everyone!

I've set rhoPimpleDyMFoam solver for centrifugal compressor (2D case)

Turbulence model : k - epsilon
Rotational speed : 10 000 rev/min and 67 000 rev / min

I've set my controlDict:

startFrom startTime;
startTime 0;
stopAt endTime;
endTime 3;
deltaT 1e-8;
writeControl adjustableRunTime;
writeInterval 1e-5;
purgeWrite 0;
writeFormat ascii;
writePrecision 10;
writeCompression on;
timeFormat general;
timePrecision 6;
graphFormat raw;
runTimeModifiable true;
maxCO 0.8;
adjustTimeStep yes;
maxDeltaT 1e-5;


I don't know why solwer is not using maxCO properly. Example:

If i set maxCO to 0.8 - it runs on CO = 1.2 - 1.4
If i set maxCO to 0.5 it runs on CO = 0.9 - 1
If i set maxCO to 0.2 it runs on CO = 0.5 - 0.6

Main problem is that after about 100 - 200 timesteps , Courant number is immidiately raising to 4 - 6 and then 10000.... and solver crushes...