appropriate BC - top half of the pipe
 

Hi,

Im simulating a pipe with a ke model, considering the top half of the pipe. My problem is with the boundary conditions. I set “velocity-inlet” and “pressure-outlet” for the inlet and outlet faces. What is the more appropriate BC for the symmetry plane? “symmetry” or “axis”? What is the difference?

*symmetry means symmetric with respect of a plane
*axis means revolution-axisymmetric with respect of an axis (solution theta-independant with theta: rotation-angle around your axis)

When you are using axis, you must work with 2d solver.

thank you very much!