Duct Liner Noise Reduction

Duct Liner Noise Reduction

NO-10
ASPCSPAdvanced

Formula
\[ NR = 12.6 \times \left(\frac{P\alpha}{A}\right)^{1.4} \]
When to Use

Predict noise reduction per foot of duct length when duct is lined with acoustic material.

Symbol Legend
SymbolMeaningUnitNote
NRNoise reduction per foot of ductdB/ft
PPerimeter of ductinches
αAbsorption coefficient of lining at frequency of interestFrom manufacturer data
ACross-sectional area of ductin²

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