The Thermoviscous Acoustics, Frequency Domain Interface, The Thermoviscous Acoustics, Transient Interface, and The Thermoviscous Acoustics, Boundary Mode Interface are designed for the analysis of acoustics in viscous and thermally conducting, compressible Newtonian fluids. The physics interface solves the linearized Navier-Stokes equation, the continuity equation, and the energy equation. This corresponds to a small parameter expansion of the dependent variables. The physics interface solves for the acoustic pressure variations p, the fluid velocity variations u, and the acoustic temperature variations T. The interface uses a scattered field formulation where it is possible to define background acoustic fields. All equations and boundary conditions are formulated in the total fields and solve for the scattered fields.

The Thermoviscous Acoustics, Frequency Domain Interface is available for 3D, 2D, and 1D Cartesian geometries as well as for 2D and 1D axisymmetric geometries. The physics interfaces solves problems in the frequency domain, that is, Frequency Domain, Frequency-Domain Modal, and Eigenfrequency type analysis. In 2D and 1D axisymmetric systems, a Mode Analysis study is also available for the out-of-plane component.

The Thermoviscous Acoustics, Transient Interface is available for 3D, 2D, and 1D Cartesian geometries as well as for 2D and 1D axisymmetric geometries. The physics interfaces solves problems in the time domain using the Time Dependent analysis type.

The Thermoviscous Acoustics, Boundary Mode Interface is available on boundaries in 3D and 2D axisymmetric geometries. The physics interface helps identify and solve for propagating and nonpropagating modes using the Mode Analysis study.