[bongbang]

I'm trying to reduce the cell count in my stent model, whose intricate geometry that requires a ridiculously high resolution on the wall. The interested quantities are only on the wall (wall shear stress) and no where else. Since the growth rate has a big impact on the cell count, I wonder how far I can raise it. I know that the best practice is to keep it no higher than than 1.2 (20%), but in my desperation I have raised it to 1.25 in my minimal model (the actual one will be 42 times as large) without much impact on my result. I am tempted to raise it further until I can't without affecting the result.

Is there an absolute limit that I should not cross under any circumstance? If there's a growth rate at which my results will simply lack credibility regardless of my assurance to the contrary, what is it? Thanks.

[hwet]

This might help

http://www.computationalfluiddynamics.com.au/tips-tricks-turbulence-part-4-reviewing-how-well-you-have-resolved-the-boundary-layer/

[bongbang]

Thanks, but my flow is laminar, so the boundary layer is not a concern.