STRANGE BUT REAL !!!!about the velocity at wall BCs
 

Hello everyone,

I was trying to explore some simple thing.
I created a simple duct, and then simple inlet outlet and walls.
amazingly, when I extracted the nodal velocity values on all wall BCs using FILE>Export>.... , they are not zero.!!!! ( walls are no-slip, though)

I extracted the velocity contours on the wall, they are zero. I shared this problem with my supervisor. and he told me that they values are being calculated on each cell centet point and then interpolated on the vertices...

Is that correct???

Yes, the at the walls are represented by volumes and actual boundaries of these volumes away from walls. So you see velocity on the wall. If you want it zero, choose hybrid velocity instead of conservative in CFD Post. http://www.cfd-online.com/Wiki/Ansys..._inaccurate.3F

I think the FAQ you were trying to reference was this one: http://www.cfd-online.com/Wiki/Ansys...t_the_walls.3F