The default condition defined by Ansys Polydata on each section of the boundary is a zero wall velocity (zero normal velocity and zero tangential velocity), except for the axis of symmetry in an axisymmetric model. For an axisymmetric model, Ansys Polydata automatically prescribes a symmetry condition along the line . You can keep the default condition where appropriate, and specify new conditions for the rest of the boundary sections. The boundary conditions available in Ansys Polydata are as follows:

It is also possible to specify conditions on a boundary section using a submodel, as described in Specifying Conditions Using Sub-Models. With sub-models, you can also specify conditions on an internal region of the domain.