[wzhang11]

Hi all

after conducted several CFD simulations, a question about timestep study has confused me, firstly, the timestep delta t can be estimated through Cr number if we know the flow velocity and minimum cell size, but in some paper i read, timestep study was still studied by half it, so why?

secondary, for the whole domain, we will have refine mesh around the structure and maybe will have prism layers, so how do u guys choose the minimum cell size to calculate delta t?

Cheers
Jason