The Incident Pressure Field node is a subnode to all nonreflecting boundary conditions (plane, cylindrical, or spherical wave radiation). From the Physics toolbar, add to Plane Wave Radiation, Spherical Wave Radiation, or Cylindrical Wave Radiation nodes. If the incident pressure field pi is a predefined plane wave, it is of the type:
where p0 is the wave amplitude, k is the wave vector (with amplitude keq=|k| and wave direction vector ek), and r is the location on the boundary. The incident pressure field can also be a user-defined value or expression.
From the Incident pressure field type list, select Plane wave to define an incident pressure field of plane wave type. Then enter a Pressure amplitude p0 (SI unit: Pa) (the default is 0 Pa) and Wave direction ek (SI unit: m).
Select User defined to enter the expression for the Incident pressure field pi (SI unit: Pa) as a function of space. The default is 0 Pa.