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Baffle Absorption   1/1,1/3

Strutt|Building Acoustics|Baffle Absorption calculates the sound absorption of a baffle system in accordance with Probst (2007) methodology.

For baffle systems, the absorption \alpha_K is calculated as follows:
\alpha_K = 1 - (\sqrt{1+a' ^2}-1)/(a')-1/(a')\sum_{n=1}^{+\infty}(1-\alpha_B)^n\cdot(\sqrt{1+((n-1)\cdota')^2}+\sqrt{1+((n+1)\cdota')^2}-2\cdot\sqrt{1+(na')^2})

Where:
a' is the baffle spacing (in metres or feet)

If the baffle system is suspended below a reflective ceiling, then the absorption coefficient \alpha_(K,W) of the system is:
\alpha_(K,W)=\alpha_K\cdot(2-\alpha_K)

If the baffle system is suspended below an absorptive ceiling, then the absorption coefficient \alpha_(Komb) of the system is:
\alpha_(Komb)=\alpha_(K,W)+\alpha_H\cdot(1-\alpha_(K,W))

Where:
\alpha_H is the absorption coefficient of the ceiling.

References:

• Probst, W. (2007) Sound Absorption of Baffle Systems, published online by DataKustik at https://www.datakustik.com/fileadmin/user_upload/e-Learning-Center/Papers-and-Publications/2007_Sound_absorption_of_baffle-systems_WP.pdf. Accessed 26th July 2023.