In the bulk, the pressure wave is typically the fastest wave and the shear wave is the slowest wave. The wave speeds can be evaluated through the variables solid.cp and solid.cs. They can be evaluated before solving a model fully, by using the Get Initial Value on the study, and then plot the variables or evaluate them in a point. If a free surface or a material discontinuity is present in the model interfacial waves will also propagate. For example, the classical estimate for the Rayleigh wave speed vR is

where ν is the Poisson’s ratio and cs is shear wave speed.

When solving elastic wave problems with the Solid Mechanics interface in the time domain, it is important to make changes to the Transient Solver Setting section (top interface node). Expand the section and select the check-box Maximum frequency to resolve, then enter the maximum frequency to resolve in the model fmax,sol (remember to reset the solver if changes are made to this section). The maximum frequency is dictated by the frequency content of the source as well as the eigenmodes of the structure that can be excited. Setting this correctly will results in a transient solver tuned specifically for modeling wave problems.