Setting Boundary Conditions and Values

The geometry used for this tutorial has six boundaries, three of which will have no-slip wall conditions assigned to them. The remaining three boundaries will be assigned inlet, pressure and symmetry boundary conditions.

We will start with the wall boundary definitions.

The Bottom boundary should be left as a symmetry boundary.

The only condition that needs to be specified for the wall boundaries is the contact angle of the glycerine-air interface.

The contact angle at the wall is given with respect to the first-defined fluid of the multiphase mixture, glycerine in this case. The latter is a wetting fluid whose free surface meets the wall at an angle of 45^o.

Next, the boundary conditions for the inlet and pressure boundaries must be set.

This in effect enforces the condition that only glycerine may enter the solution domain through that boundary.

This in effect enforces the condition that only air may enter the solution domain through that boundary.

This completes the boundary condition specification.