Hi @Get_Barried and @vyvo
yes it is hard to say what is too high, if a flow is ‘steady’ then it might be ok to push that far, however, the ability can depend upon many things such as turbulence model, and velocity fluctuations particularly present if using LES. Also, In terms of actual speed up form pushing courant number, I haven’t so far seen much due to the increase of outer iterations and reduction in relaxation factors required. Setting the outer iterations to 1 and the relaxation to 1, as well as max courant number to about 0.5 has given me some fast results, but a stable setup would be relaxation around 0.5-0.7 with outer iterations from about 5-50.
Best,
Darren