Example1 Harmonic analysis

General

• The model is a piezoelectric disc. The AC voltage applied across the top and bottom faces generates the vibration.
  The sound waves are radiated as a result.
   

• This is a piezoelectric-acoustic coupled analysis.
   

• Unless specified in the list below, the default conditions will be applied.

• Please set the analysis domains in body attributes properly.
  Follow the settings on Body Attributes and Material Properties below.
   

Analysis Space

Analysis Conditions

The solvers are Rayleigh and Mach.

The harmonics analysis tab is set up as follows.

The sound waves propagate outside the analysis region. Therefore the “open boundary” condition below is applied initially.

Model

A piezoelectric disc (Unit) is placed on an aluminum disc (Plate). The hemispheric body (Air) covers the upper area.

Body Attributes and Materials

* Available from the Material DB

Unit and Plate are for the piezoelectric analysis only, whereas Air is for the acoustic analysis only.

Cautions:

In this analysis, it is necessary to specify the analysis domain.

Specify either piezoelectric analysis or acoustic analysis as the usable domain on the analysis domain tab.

Boundary Conditions

The side periphery of the model is fixed in the Z direction.

Electric wall is set on the top and bottom faces of the piezoelectric disc.

The open boundary is set on the hemispheric surface.

Results

The magnitude of displacement is shown below.

The largest displacement is indicated in the center area.

The contour of the sound pressure on the XZ section is shown below.

The sound waves are propagating from the top of the device.