I am having difficulties implementing the Grille boundary condition in Laminar flow (spf) in COMSOL 5.2a.
Whether I set the quadratic loss coefficient (qlc) under the Grille Boundary node to zero or any non-zero value, I get the same result.
As an example, I tested it for a simple pipe flow with an inlet (which is treated as a grille boundary with pressure boundary condition) and an outlet (also with a pressure boundary condition). Please see the attached .mph file. You can see by running the file for various values of qlc or 'static pressure curve data' that the pressure profile along the length of the pipe does not vary, nor does the flow rate.
It looks like the Grille boundary condition is not working; that is, it is not implementing a pressure drop due to the presence of the 'grille'.
Could somebody please help me figure out the solution to the problem. Thanks.