Acoustic Impedanceexamples|products|Murata Software Co., Ltd.

Example7 Acoustic Impedance

General

 

  • No reflection is observed when the “acoustic impedance” boundary condition is set.
     

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

 

Analysis Space

Item

Settings

Analysis Space

3D

Model unit

mm

 

 

Analysis Conditions

Item

Settings

Solver

Acoustic Analysis [Mach]

Analysis Type

Static analysis

Options

N/A

 

 

Tab

Setting Item

Settings

Harmonic analysis

Frequency

Minimum: 50[KHz]

Maximum: 50[KHz]

Model

A vertical pipe is jointed on a horizontal pipe. Sound waves go in the vertical pipe and exit through the horizontal pipe.

The “Acoustic impedance” boundary condition is set on the sections of the horizontal pipe.

That makes the horizontal pipe reflection-free.

 

 

 

Body Attributes and Materials

Body Number/Type

Body Attribute Name

Material Name

0/Solid

AIR

000_Air(*)

* Available from the Material DB

 

Boundary Conditions

Boundary Condition Name/Topology

Tab

Boundary Condition Type

Settings

Vel/Face

Acoustic

Speed

1[m/s]

Imp/Face

Acoustic

Acoustic impedance

409.7[Pa*s/m]

(the value for air)

 

 

Results

The isosurface contour of the sound pressure is shown below.

 

 

Create the animation to see the sound waves flow better.