BEM (Boundary element method) Acoustics requires only surface mesh of the source body for both internal cavity sound propagation or transmission, and for external sound propagation for radiation. You can either close openings (holes) to create watertight acoustic cavity for internal sound propagation or does not close openings for external sound radiation. You can use Wrap to create the surface mesh and remesh the surface with quadrilateral elements to improve surface mesh quality and reduce the mesh count. For External BEM Acoustics, a microphone grid surface of hemispherical shape can be created for results postprocessing using Create Enclosure step.
Note: BEM Acoustics mesh has linear element by default. Hence, BEM Acoustics recommends a minimum of 8 elements per wavelength of sonic speed of medium.
When you select Mesh Workflows as BEM Acoustics, Mesh Workflow loads a predefined template with Steps and Outcomes. Mesh Workflow performs these Steps through Controls and Outcomes to achieve the desired mesh for the BEM Acoustics.
BEM Acoustics workflow has the following steps:
Fill Holes: Fill the holes defined in the Hole Filling step. The operation type available for Fill Holes is Fill Holes.
Wrap Parts: Wraps the selected parts. The operation type available for Wrap Parts is Wrap.
Improve Wrap Mesh: Improves the surface mesh. The operation type available for Improve Wrap Mesh is Mesh Surface.
Quad Based Remesh: Remesh the surface to convert the tri-based mesh into a quad-dominant mesh. The operation type available for Quad Based Remesh is Mesh Surface.
Quad Based Remesh uses Constant Size Surface Mesher for remeshing.
Create Enclosure: Creates the enclosure around the specified scope. The operation type available for Create Enclosure is Create Enclosure.
Create Acoustic Regions: Creates the topology from the mesh only model. The operation type available for Create Acoustic Regions is Create Topology.
Assign Physics Properties: Defines material properties and thickness on the scoped parts or zones. The operation type available for Assign Physics Properties is Manage Zone Properties.