Learning Forum

[miraba2]

In this post, Ansys acoustics Harmonic responce problem user Erik Kostson advises not to use ACT acoustics extension, is it depricated, or is there another reason? I am following a text  Acoustic Analyses Using
MATLAB®
and ANSYS®
Carl Q. Howard and Benjamin S. Cazzolato and none of the examples work - the question mark by acoustic mass source can't be resolved to check  

[peteroznewman]

The functionality that was enabled by the old acoustic ACT extensions is no longer needed since most of the functionality is now included in the native Mechanical app. I am using Ansys Student 2024 R2 and I can select Harmonic Acoustics instead of Harmonic Response. Air is automatically included in the list of materials. In Mechanical, under Geometry, click on the solid body and assign Air to the solid cubic body.  

To get rid of the ? on the Analysis Settings, enter the Frequency Range Maximum.

Right click on Mesh to create a mesh. You should select an element size so that six quadratic elements will be created for one wavelength of the maximum frequency you requested.

Click on the Harmonic Acoustics branch of the Outine and on the Context Environment tab, you can see a drop down button for Acoustic Excitations, select Mass Source. I tried to assign a Mass Source to a node in a Named Selection, but it would not take that. It seems there are still some gaps in the functionality.  I was able to assign a Mass Source to a Vertex, so as a work around, I had to go and make a vertex in the cube geometry first.

[miraba2]

Is there an equivalent for 'fsi' in the new harmonic acoustics module? Thanks

[Erik Kostson]

 

Yes – if structure and acoustic domain are sharing topology (best option), got to the harmonic acoustic (A6) on the tree (where we insert loads, bc, etc) and insert this FSI, or even better since it is done automatic (it will find pair of faces that are connected via shared topology used in Discovery, Spaceclaim or Design mod.) right mouse button click and choose create automatic -> FSI.

See this chapter for details:

2024 R2 > Mechanical Acoustic Analysis Guide > 2.1. Harmonic Acoustics Analysis

 

[peteroznewman]

Six years ago, I made this video to take vibration of a tuning fork and compute the acoustics in the air around it.

Here is a video on the vibration of a plate.

There are several free courses in Acoustics that use more recent versions of Ansys.  Here is a list.

One of the lessons shows a more recent version of a vibrating plate causing an acoustic response.