Low-Reflecting Boundary
Use the Low-Reflecting Boundary node to let waves pass out from the model without reflection in time-dependent or frequency domain analysis. As a default, it takes material data from the domain in an attempt to create a perfect impedance match for both pressure waves and shear waves. It can be sensitive to the direction of the incoming wave.
The Low-Reflecting Boundary node is only available with some COMSOL products (see http://www.comsol.com/products/specifications/).
Damping
Select a Damping typeP and S waves (the default) or User defined. For User defined enter values or expressions for the Mechanical impedance di. The defaults for all values are 0.5*solid.rho*(solid.cp+solid.cs).
Location in User Interface
Context Menus
Solid Mechanics>Mass, Spring, and Damper>Low-Reflecting Boundary
Ribbon
Physics tab with Solid Mechanics selected:
Boundaries >Mass, Spring, and Damper>Low-Reflecting Boundary