Reply To: What is the reason of Absorbtion Coefficient too small or zero on Impedance Tube Simulation?

[Erik Kostson]

Hi

I do not have an example of this. Also have in mind that ansys employees are not allowed to share any models .
All the material properties is something a user needs to input, so up to the user.

As we said now the JCA Perforated material models are pure acoustics and have only pressure dof so no need to restrain them thus- if it is glued say to a steel plate say then you can you include a structure but then the steel plate needs to have some restrains if it is has it in reality of course, since it has translational degrees of freedom. Again have in mind what we said many times, that only the perforated material model (e.g.,Delany-Bazley) will provide some absorption of acoustic energy, the steel plate can not do that (as we said it can not absorb acoustic energy). Of course it can reflect acoustic energy since it provides a different impedance to the air thus reflecting back energy acting like an acoustic barrier, but it can not absorb acoustic energy (say converting it to heat or viscous losses like perforated model does - this is inbuilt in the perforated material model formulation - see help manual for more info).

All the best

Erik