Hi! Everyone Someone told me in order to obtain good converged results I need to keep the grid aspect ratio low too. But how about at the boundary layer? A.R usually high at the boundary layer.

the key is how low is low...10 or 100 or 1000

I usually consider something at about AR = 10~20 as acceptable. And depends on the local flow velocity so for something of high subsonic it would be better to keep it below 10.