physical time scale && advection time
 

Hi,
I am simulating steady state flow over a hydrofoil, but it doesn't converge to error less than 1e-4. I have read alot about the effects of time scale on the convergence, but still do'nt know how I can choose an appropriate physical time scale based on the advection time (reported at the end of out file). I mean is there any relationship between these parameters?
thanks,

If you have no idea about the physical time scale for your problem, I think it's better to choose automatic time instead. it should be noted that sometimes bad mesh quality leads to high residuals and you cannot reduce them even by setting a very small timescale.

This FAQ covers it: http://www.cfd-online.com/Wiki/Ansys...gence_criteria

In your case as you have a free surface it is highly likely that a steady state result is not possible (or at least not easy) and you will have to run transient to get it to converge.