Generators, especially diesel ones, can be very loud. This is a problem, as they can damage the hearing of those who have to work in close proximity to them and be a nuisance for those who work or live nearby. In order to combat this problem, silent generators were created. A silent generator operates inside a soundproof container or generator enclosure which will muffle the sound of a generator.

Silent Generator

Silent diesel generators use composite materials in a generator enclosure. Usually, these are layers of hard material which bounce the sound energy back into the enclosure. They also use soft, porous materials which absorb the sound energy, converting it into heat.

Different materials absorb different sound frequencies better than others. Some materials might be very good at absorbing sound at high frequencies, but poor at the lower end. To combat this, most silent generators use different materials in several layers.

Higher frequencies are best absorbed by porous materials, which channel the smaller sound waves deep into the material which then absorbs them. Lower frequency sounds are harder to silence. The waves of lower frequency sounds are sometimes deflected or absorbed by heavy layers of material, which are resistant to movement. The best results for deadening lower frequencies come from using air pockets. Thin panels of material are separated by shallow air gaps. This creates a resonance effect to make the low-frequency sound into a higher pitch. This pitch can then be better absorbed by the porous materials.

A generator enclosure will be engineered for a particular type of generator or a specific model, in order to make sure the soundproofing is as effective as possible at absorbing the range of sound produced the generator.