[ati_ros61]

Dear F3D experts,
I am trying to simulate the free surface flow over rough bed (Ks=0.005 to 0.05m). I have some questions:
1-What's happen If the mesh sizes is smaller than roughness?
2-I set rough=ks, Is any other changes needed?
3-In rough bed problems, the boundary layer is too small and negligible. Can I use free slip condition in this problem? and how about "FRCOF"?

Regards

[Andy Chen]

Originally Posted by ati_ros61

Dear F3D experts,
I am trying to simulate the free surface flow over rough bed (Ks=0.005 to 0.05m). I have some questions:
1-What's happen If the mesh sizes is smaller than roughness?
2-I set rough=ks, Is any other changes needed?
3-In rough bed problems, the boundary layer is too small and negligible. Can I use free slip condition in this problem? and how about "FRCOF"?

Regards

Good questions, maybe you can reference Modeling Roughness Effects in Open Channel Flows ( Souders and Hirt, 2002)

http://www.flow3d.com/pdfs/tn/FloSci-TN60.pdf

Regards