The noise - sound power level - generated in single opposed blade dampers can be estimated from the chart below:
- 1 mm water H2O = 9.81 Pa = 9.81 N/m2 = 1 kg/m2 = 0.0736 mm mercury = 0.9677 10-4 atm = 0.00142 psi = 0.0394 in H2O
The noise level generated depends on the volume flow through the damper and can be corrected using the table below
Room acoustics and acoustic properties, decibel A, B and C, Noise Rating (NR) curves, sound transmission, sound pressure, sound intensity and sound attenuation.
Noise is usually defined as unwanted sound - noise, noise generation, silencers and attenuation in HVAC systems.
The sound generated by a fan depends on the motor power, the volume capacity, the static pressure increase and the discharged volume.
Pressure head loss in HVAC dampers.
Sound attenuation vs. frequency in rotating heat exchangers.
The logarithmic decibel scale is convenient when adding signal values like sound power, pressure and others from two or more sources.
Introduction to decibel, sound power, intensity and pressure.
Sound power from sources like fans, jet engines, cars, humans and more.