Use the Wall node to model the most common conditions at solid surfaces. This is the default boundary condition. This condition contains both a mechanical and a thermal selection. The default is a no-slip and isothermal condition applicable in most cases.

For the acoustic pressure, the wall condition represents the natural Neumann condition. For the viscous scaling function, a no-slip condition represents a constraint Ψv = 0, while for the thermal scaling function, an isothermal condition represents a constraint Ψth = 0.

Select the Mechanical condition as No slip (the default) or Slip (perfect).

The choice made for the mechanical condition is inherited by the Normal Acceleration, Normal Velocity, Normal Displacement, Impedance, and Lumped Speaker Boundary features if added to the same boundary.

Select the Thermal condition as Isothermal (the default) or Adiabatic.

The choice made for the thermal condition is inherited by the Normal Acceleration, Normal Velocity, Normal Displacement, Impedance, and Lumped Speaker Boundary features if added to the same boundary.

These settings are shown when the Advanced Physics Options is selected. It controls how the constraints are handled.