3.21. Far-Field Radiation Surface

This boundary condition enables you to define the Maxwell surface for Far-field parameters.

Analysis Types

The Acoustic Far-Field Radiation Surface loading condition is available for Coupled Field Harmonic and Harmonic Acoustics analyses.

Common Characteristics

This section describes the characteristics of the boundary condition, including the application requirements, support limitations, and loading definitions and values.

Dimensional Types

3D Simulation: Supported.
2D Simulation: Not Supported.

Geometry Types: Geometry types supported for the Far-Field Radiation Surface boundary condition include:

Solid: Supported.
Surface/Shell: Not Supported.
Wire Body/Line Body/Beam: Not Supported.

Topology: The following topology selection options are supported for Far-Field Radiation Surface.

Body: Supported.
Face: Supported.
Edge: Not Supported.
Vertex: Not Supported.
Nodes: Not Supported.
Element Face: Not Supported.
Element: Not Supported.

Loading Data Definition: Not applicable.

Boundary Condition Application

To apply an Far-field Radiation Surface:

On the Environment Context tab: select Acoustic Boundary Conditions > Far-Field Radiation Surface. Or, right-click the Environment tree object or click in the Geometry window and select Insert > Acoustics > Far-Field Radiation Surface.
Define the Scoping Method.

Details View Properties

The selections available in the Details view are described below.

Category	Fields/Options/Description
Equivalent Surface Selection	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 (Face selection only): Visible when the Scoping Method property is set to Geometry Selection. Geometry selections must be made on bodies specified in the acoustic Physics Region. Use the Face selection filter to pick your geometry, click in the Geometry field, and then click the Apply button that displays. After you select the geometry, this property displays the geometric entities (1 Face, 3 Faces, etc.). 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 (face-based only).
Inside Surface Bodies	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 (Face selection only): Visible when the Scoping Method property is set to Geometry Selection. Geometry selections must be made on bodies specified in the acoustic Physics Region. Use the Face selection filter to pick your geometry, click in the Geometry field, and then click the Apply button that displays. After you select the geometry, this property displays the geometric entities (1 Face, 3 Faces, etc.). 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 (face-based only).
Definition	Type: Read-only field that describes the object - Far-Field Radiation Surface. Suppressed: Include (No - default) or exclude (Yes) the boundary condition.

Category

Fields/Options/Description

Equivalent Surface Selection

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 (Face selection only): Visible when the Scoping Method property is set to Geometry Selection. Geometry selections must be made on bodies specified in the acoustic Physics Region.
  Use the Face selection filter to pick your geometry, click in the Geometry field, and then click the Apply button that displays. After you select the geometry, this property displays the geometric entities (1 Face, 3 Faces, etc.).
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 (face-based only).

Inside Surface Bodies

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 (Face selection only): Visible when the Scoping Method property is set to Geometry Selection. Geometry selections must be made on bodies specified in the acoustic Physics Region.
  Use the Face selection filter to pick your geometry, click in the Geometry field, and then click the Apply button that displays. After you select the geometry, this property displays the geometric entities (1 Face, 3 Faces, etc.).
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 (face-based only).

Definition

Type: Read-only field that describes the object - Far-Field Radiation Surface.

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

Mechanical APDL References and Notes

This boundary condition is applied using MXWF label of the SF command. For more information, refer to the Equivalent Surface Source section in the Mechanical APDL Acoustic Analysis Guide.

API Reference

See the Far-field Radiation Service section of the ACT API Reference Guide for specific scripting information.