Number of CFL and computing time

ds2taieb

Hello,

I'm trying to compute several cases with Open Foam to compare with Fluent results.
My first case is a 2d straight plane with a velocity inlet at left, an outflow at the top and the right and a wall condition at the bottom.

My second case is a tunnel in three dimensions with lateral wall, a velocity inlet, and an outflow.

So with Fluent my first case required about 20 minutes to be converged and my second 30 minutes. With OpenFoam I have set the Courant Number round 0.7. The computation time is too long and I want to improve this time.

So is it possible to use an scheme which is stable for every courant number as "segregated" and "coupled-implicit" in Fluent.

Greetings