Pair Acoustic-Structure Boundary, Time Explicit

The multiphysics coupling (

) is used to couple the Pressure Acoustics, Time Explicit interface with the Elastic Waves, Time Explicit interface, in an assembly geometry where identity pairs have been created.

This pair version of the coupling makes it possible to take full advantage of the time explicit formulation, where the global time step is controlled by the minimum all local mesh based time steps (complying with the local CFL condition). That is using a mesh size based on the local minimum wave speed cmin, as the mesh sizes do not need to be conforming where the fluid and the solid domains meet. The local mesh size hmax should always comply with

where N depends on the element approximation order (1.5-2 for the default settings) and fmax is the maximum frequency to resolve. There will often be a clear advantage in the computation time using the over the feature due to a larger internal time step and in general fewer degrees of freedom solved for.

Settings

See Settings for further details about and .

The default (for the first multiphysics coupling feature in the model) is aspte1.

Coupled Interfaces

This section defines the physics involved in the multiphysics coupling. The and lists include all applicable physics interfaces. Only The Pressure Acoustics, Transient Interface and The Elastic Waves, Time Explicit Interface can be selected here.

Pair Selection

Add and select the identity pairs where the pair multiphysics coupling feature is applied.


	Create separate Identity boundary Pairs for components of the boundary (where the coupling feature is used) if they meet at a corner or sharp edge. One identity pair for each boundary. By default, identity pairs are created automatically when forming an assembly. Use the automatically created identity boundary pair, duplicate it and then edit them removing boundaries, where necessary.