3.5. Port In Duct

You use the Port In Duct excitation condition is used to create an incident wave and acoustic duct ports.

Analysis Types

The Port In Duct 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.

Scoping

The Port In Duct excitation scoped using the Port object.

Loading Data Definition

The Port In Duct excitation condition is defined as a constant only.

Boundary Condition Application

To apply a Port In Duct:

  1. On the Environment Context tab: select Acoustic Excitations > Port In Duct. Or, right-click the Environment tree object or click in the Geometry window and select Insert > Acoustics > Port In Duct.

  2. Define Port Attribution, Wave Type, Coordinate System.

  3. Define Pressure Amplitude & Phase Angle

  4. Define Width, Height, and Mode indices along width and height for Wave Type = Rectangular Duct

  5. Define Radius, and Mode indices along azimuth and radii for Wave Type = Circular Duct

  6. Select a Port from the available Ports

Details View Properties

The selections available in the Details view are described below.

CategoryFields/Options/Description
Definition

Type: Read-only field that describes the object – Port In Duct.

Port Attribution: This property provides the options Inlet and Outlet.

Wave Type: This property provides the following options.

  • Planar Wave

  • Rectangular Duct

  • Circular Duct

Coordinate System: Drop-down list of available coordinate systems. Global Coordinate System is the default. The Local Coordinate System should be chosen such that the cross section of Port in Duct lies in X-Y Plane.

Specification of the following inputs are required based on Wave Type.

  • Pressure Amplitude: Input specify excitation pressure amplitude. Only available for Port Attribution Inlet.

  • Phase Angle: Input to specify the phase angle.

  • Angle Phi (From X Axis Toward Y Axis): Input available for Wave Type = Planar Wave.

  • Angle Theta (From Z Axis Toward X Axis): Input available for Wave Type = Planar Wave.

For Wave Type = Rectangular Duct, define the following rectangular duct properties:

  • Width

  • Height

  • Mode index for pressure variation along the width

  • Mode index for pressure variation along the height

For Wave Type = Circular Duct, define the following circular duct properties:

  • Radius

  • Mode index for pressure variation along the azimuth

  • Mode index for pressure variation along the radii

Port Selection: Select a port from drop-down list of available valid ports. The Vibro option for Port Behavior is supported.

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

Mechanical APDL References and Notes

The command APORT is used to apply the Acoustic Port In Duct excitation condition. For more information, refer to the Specified Mode Excitation in an Acoustic Duct section in the Mechanical APDL Acoustic Analysis Guide.

API Reference

See the Port In Duct section of the ACT API Reference Guide for specific scripting information.