The Thermoviscous Acoustic-Solid Interaction, Frequency Domain Interface
The Thermoviscous Acoustic-Solid Interaction, Frequency Domain multiphysics interface (), found under the Thermoviscous Acoustics branch () when adding a physics interface, combines the Thermoviscous Acoustics, Frequency Domain and Solid Mechanics interfaces. The physics interface solves for, and has predefined couplings between, the displacement field in the solid and the acoustic variations in the fluid domains.
The physics interface solves the equations in the frequency domain assuming all fields and sources to be harmonic. Linear acoustics is assumed.
When a predefined Thermoviscous Acoustic-Solid Interaction, Frequency Domain interface is added from the Acoustics>Thermoviscous Acoustics branch of the Model Wizard or the Add Physics windows, the Thermoviscous Acoustics, Frequency Domain and Solid Mechanics interfaces are added to the Model Builder.
In addition, the Multiphysics node is added, which automatically includes the multiphysics coupling Thermoviscous Acoustic-Structure Boundary.
Settings for Physics Interfaces and Multiphysics Couplings
When a predefined multiphysics interface is used, for example Thermoviscous Acoustic-Solid Interaction, Frequency Domain, the Selection on the multiphysics coupling is automatically set to All boundaries. In this way, the multiphysics coupling is automatically active on all boundaries with Thermoviscous Acoustics, Frequency Domain on one side and Solid Mechanics on the other.
However, if physics interfaces are added one at a time, followed by the multiphysics couplings, these modified settings are not automatically included.
For example, if the single interfaces are added, COMSOL Multiphysics adds an empty Multiphysics node. You can choose the available multiphysics couplings, but you need to manually select on which boundaries they need to be applied, or select All boundaries to recover the predefined behavior.
Multiphysics couplings are available from the context menu (right-click the Multiphysics node) or from the Physics toolbar, Multiphysics menu.
Physics Interfaces and Multiphysics Couplings
Multiphysics Coupling
See Thermoviscous Acoustic-Structure Boundary in the Multiphysics Couplings chapter.
Physics Interface Features
Physics nodes are available from the Physics ribbon toolbar (Windows users), Physics context menu (Mac or Linux users), or right-click to access the context menu (all users).
In general, to add a node, go to the Physics toolbar, no matter what operating system you are using. Subnodes are available by clicking the parent node and selecting it from the Attributes menu.