Acoustic Insulation And Noise Control: Frequencies And Sources

By Author: Henry Janice
Total Articles: 139
Comment this article

Acoustic insulation transmits, absorbs or redirects sound, a type of energy that travels in waves. Undesired sounds or noise are simply unpleasant to hear. They can damage human health, jeopardize the safety of the worker, and is conducive to structural fatigue.
The results of noise can be serious, but its features are seldom misunderstood.
Sources of noise
Noise can be caused by mechanical vibration. Mechanical vibration induces resonance in structures like equipment, machinery and vehicles.
Military vehicles and mobile equipment are vulnerable to all three noise sources. Mechanical vibrations from the engine bay of a vehicle can enter the cabin interiors. Friction happens during vehicle braking, specifically with sudden stops. Air flow across the exterior of a vehicle can also cause undesired sounds.
Designers of equipment, infrastructure and aircraft face same kind of challenges. Fans, wind turbines, helicopter rotors and airplane flaps have turbulent air flows around their edges. Light fittings and HVAC systems can induce mechanical vibrations.
Noise control and ...
... frequency
Frequency is a vital feature of sound and thereby creates the demand for Chicago noise control. Hertz (Hz) the unit of measure that is used for frequency is the number of oscillators per second in a sound wave. High frequency sounds have short distances between oscillations. Low frequency sounds have longer distances. That is nice to know from a scientific perception, but what are the implications for acoustic insulation?
Physical barriers are less effective against low frequency sounds like the rumble of the diesel engine. When the noise source and its receiver are on different sides of a barrier, the aim is to block the sound. This is why in military vehicles and mobile equipment, acoustic insulation is attached to the firewall that segregates the engine bay from the cabin.
Sound absorption is not the only technique of Aurora noise control. In buildings, physically segregating the two sides of a wall makes it difficult for sound to pass through. Known as decoupling, this soundproofing technique uses acoustic insulation as the medium between two panels. Decoupling may turn out to be effective, but only at frequencies where resonance levels won’t induce mechanical vibrations and more noise.
As Naperville noise control techniques, decoupling and sound absorption are effective when the source and the receiver are on different sides of a screen, wall, equipment enclosure or other barrier type. When the receiver and the sound are on the same side, it is vital to restrict the reflection of the sound rather.    
Acoustic radiation is complicated. Technical buyers, engineers and product designers should know more than just the decibel level. Both the sound source and its frequency are vital design considerations. Acoustic insulation can also be tuned to allow or prevent the passage of particular frequency ranges. Custom fabrication, design assistance and testing services can strengthen your application.