The Mechanical Damping subnode allows you to model mechanical losses in the Piezoelectric Material, either via using the loss factor material data for the stiffness, or in form of the Rayleigh proportional damping.

Select a Damping type — Loss factor for cE (the default), Isotropic loss factor, or Rayleigh damping.

By default the Loss factor for elasticity matrix cE ηcE uses values From material. For User defined enter other values or expressions in the matrix.

By default the Isotropic structural loss factor ηs uses values From material. For User defined enter another value or expression.

Enter the Mass damping parameter αdM and the Stiffness damping parameter βdK.

In this damping model, the damping parameter ξ is expressed in terms of the mass m and the stiffness k as

That is, Rayleigh damping is proportional to a linear combination of the stiffness and mass; there is no direct physical interpretation of the mass damping parameter αdM and the stiffness damping parameter βdM. Note that the beta-damping is applied only to the mechanical part of the problem. To include the Rayleigh damping effect for the piezoelectric coupling terms, add a Coupling Loss subnode.

Physics tab with Piezoelectric Material node selected in the model tree:
Attributes>Mechanical Damping