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Toktom / PyAbsorp

PyAbsorp is a python module that has the main focus to help estimate the Sound Absorption Coefficient using analytical models.
MIT License
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Johnson-Champoux-Allard-Pride-Lafarge Model Implementation #2

Open Toktom opened 4 years ago

Toktom commented 4 years ago

I was trying to implement the Johnson-Champoux-Allard-Pride-Lafarge model, but I'm stuck because I didn't understand how to obtain the Static Viscous Tortuosity and the Static Thermal Tortuosity required in the mathematical formulation. I did some research and I dind't find anything that could help me. I looked into the book Propagation of Sound in Porous Media by Jean F. Allard and Noureddine Atalla but the explanation about Static Viscous Tortuosity it's pretty short and a bit abstract to comprehend, and I didn't find anything around Static Thermal Tortuosity. I was following the version of the mathematical formulation presented in the website APMR (Acoustical Porous Material Recipes). If someone has any suggestion to how I figure it this problem out, please contact me.

Chum4k3r commented 4 years ago

I've read a bit of the articles quoted in your reference and, I might have got it wrong, but it seems that as the majority of the parameters are frequency dependent, and get prepended the dynamic name, the static name stands for "frequency almost 0", so it would be the Viscous Tortuosity for frequency almost zero and Thermal Tortuosity for frequency almost zero.

I'm saying this as an assumption based on the other two also named static parameters: Static Air Flow Resistivity and Static Thermal Permeability.

Hope it helps on the discussion. Your code is awesome!