FMDenaro |
May 25, 2020 15:34 |
Quote:
Originally Posted by Gang Wang
(Post 771843)
Thanks for your quick reply!
My flow problem is quite esay to understand: 3D simulation of Flow around the circular cylinder at Re=3900, just want to carry out a benchmark test to validate my DNS code is feasible. I think the largest integral length scale is not the length of my domain, maybe width or height? Any suggestions?
Best,
Gang
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As Paolo wrote, you can assume that the integral length scale is of the order of the diameter. Your domain must be enough long and large to allow a physical correlation of the structures at such length. I suppose you assume periodic condition in spanwise direction and the extension must be enough wide.
In case of a DNS you need of a grid that must be refined in the BL in such a way that at least 3-4 nodes are at y+<1 (y+ is nothing but the local Re number measured in direction normal to the wall). This constraint is valid also for a resolved LES. In the latter case you can use a larger grid size in spanwise direction.
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