Dear Harrish Sajiv ;

Based on my little knowledge about the ANSYS Analytical software, you can simulate any real condition especially the fluid system. Sound transmission is also known as one of the main fluid elements which could be simply simulated via the ANSYS software. During simulation procedure, knowing the sound pressure level and the sound power level as the main elements of sound (noise) transmission is required. 

When you have detailed about the sound pressure and power levels which is transmitted through a porous structure, you can simply calculate the value of noise absorbency of your considered structure. This kind of simulation is normally used to measure the ability of a given material for absorbing the noise. But I don't know what do you mean by "calculating the noise"?!! Why you are forced to calculate the noise? I think you are required to to measure the ability of noise absorbency of the materials in terms of the level of noise reduction coefficient.

I wish, the given information could be helpful;

with the best regards;

Sanaz Hassanzadeh

PhD Student at Textile Engineering;

Isfahan University of Technology, IRAN.