Use the Low-Reflecting Boundary node to let elastic waves pass out from the model with minimal reflections. 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. The condition is sensitive to the direction of the incoming wave and works best for normal incidence.

The Low-Reflecting Boundary should be used in combination with the Absorbing Layers in Elastic Waves, Time Explicit to create efficient absorbing conditions (sponge layers) that work for most angles of incidence. The condition should be added at the outside of the absorbing layer.

Select a Damping type — P and S waves or User defined. For User defined enter values or expressions for the Mechanical impedance di. The defaults for all values are 0.5*elte.rho*(elte.cp+elte.cs) (on the diagonal for the Diagonal and Symmetric options).