[@E18]

Hi,

Has anyone used RANS for simulating any moving boundaries (no slip walls)? What are disadvantages of RANS for such problems? I am dealing with separations at the wall as well.

Thanks,
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[FMDenaro]

You should consider URANS ... A similar flow problem where URANS is quite common is the flow motion during the cycle of a piston in a cylinder. Check in literature for that

[venturi]

A known RANS/URANS model that can treat separation effects is the two-layer k-epsilon. But I don't know if it is good for moving wall.

[@E18]

Originally Posted by FMDenaro

You should consider URANS ... A similar flow problem where URANS is quite common is the flow motion during the cycle of a piston in a cylinder. Check in literature for that

Oh, thanks! By RANS I meant URANS. I will check out the piston motion literature.

[@E18]

Originally Posted by venturi

A known RANS/URANS model that can treat separation effects is the two-layer k-epsilon. But I don't know if it is good for moving wall.

Thanks Venturi for your reply. Most k-e models use damping functions for low Re numbers and apparently this causes many issues. But thanks for your comment, I will read more about it.

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