Lined Sheet-Metal Ducts - Sound Attenuation
Noise attenuation in rectangular straight, lined, sheet metal ducts. Calculate total sound attenuation based on duct dimensions, lining thickness, frequency, and duct length.
Lined Sheet-Metal Ducts - Sound Attenuation
Noise attenuation in rectangular straight, lined, sheet metal ducts.
Theory
Attenuation in ducts with 25 mm lining and 50 mm lining varies by duct dimensions and frequency.
Conversion Factors
- 1 in = 25.4 mm
- 1 ft = 0.3 m
Example Calculation
The sound attenuation in a 610 × 610 mm lined duct is approximately 2.5 dB/m at frequency 250 Hz. The total sound attenuation in a 10 m duct:
(10 m) × (2.5 dB/m) = 25 dB