3.11. Pressure

You can specify pressure on desired fluid regions in an acoustic analysis by inserting a Pressure object.

This boundary condition can be scoped only to face/edge/vertex of a body in acoustic domain. Refer to Pressure Boundary section of Mechanical APDL Acoustic Analysis Guide for more information.

Analysis Types

The Pressure loading condition is available for Coupled Field Harmonic, Coupled Field Modal, Coupled Field Transient, Harmonic Acoustics, Modal Acoustics, and LS-DYNA Acoustics analyses.

Dimensional Types

The Pressure loading condition is only supported for 3D simulations.

Geometry Types

The Pressure boundary condition only supports Solid geometry types.

Topology Selection Options

The following topology selection options are supported for Pressure.

  • Face

  • Edge (Not supported for LS-DYNA analyses.)

  • Vertex (Not supported for LS-DYNA analyses.)

Magnitude Options

Magnitude values for this boundary condition are always defined as a constant.

Boundary Condition Application

To apply a Pressure:

  1. On the Environment Context tab: click Acoustic Boundary Conditions>Pressure. Or, right-click the Environment tree object or in the Geometry window and select Insert>Acoustics>Pressure.

  2. Define the Scoping Method.

  3. Define the Magnitude of the pressure.

Details View Properties

The selections available in the Details view are described below.

CategoryFields/Options/Description
Scope

Scoping Method, options include:

  • Geometry Selection: Default setting, indicating that the boundary condition is applied to a geometry or geometries, which are chosen using a graphical selection tools.

    • Geometry: Visible when the Scoping Method property is set to Geometry Selection. Specified geometric entities must be in the acoustic Physics Region. (For LS-DYNA Acoustics systems the geometry is scoped to shell bodies and there is no acoustics physics region.)

      Use the selection filter to pick your geometry, click in the Geometry field, and then click the Apply button that displays. This property displays the type of geometry (Face, Edge, etc.) and the number geometric entities (1 Face, 3 Faces, etc.) to which you have applied the boundary condition. (For LS-DYNA Acoustics systems only Faces are supported.)

  • Named Selection: Indicates that the geometry selection is defined by a Named Selection.

    • Named Selection: Visible when the Scoping Method is set to Named Selection. This field provides a drop-down list of available user–defined Named Selections.

Definition

Type: Read-only field that describes the object - Pressure.

Magnitude: Enter a constant pressure value.

Suppressed: Include (No - default) or exclude (Yes) the boundary condition.

Mechanical APDL References and Notes

The Pressure boundary condition is applied using the PRES label of D command.