[Bollonga]

Hi everybody guys,

I'm solving a wind turbine starting with the steady laminar case and using a pressure-based coupled algorithm.

I have a few questions about the setup. I've looked at the theory guide but I don't know how the Courant number (the solver one, no the regular one) affects convergence. The only thing theory guide says is 1/CFL=(1-alpha)/alpha.

I increased CFL from default 200 to 200000 but then I reduced it to 200 as it seemed to increase computational cost. Residuals went up so I had to reduce uder-relaxation factor (URF) to half of its value for momentum and pressure (0.75 to 0.375 each).
Now that residuals are starting to go down I would like to increase computational speed as it is way too slow.
I know increasing URF will improve that, but what about CFL?

For a 1.7 Gb mesh, 8 cores parallel, 12 Gb RAM it's taking 45 min for each step.

Also, I will have to do a transient laminar case and steady/transient k-omega SST, which solver setup should I use? SIMPLEC? PISO?

Thanks in advance!