Dedicated Absorber Systems
For areas with even more focus on the noise absorption, dedicated absorbers should be fi tted. It will then be possible to take into account the resonance frequencies. The basic principle is to mount the Rockwool Slab in a calculated distance from the bulkhead / deck. Hereby it is possible to combine the principles of porosity absorbers and resonance absorbers.
Mentioned formula below gives us the possibillity to calculate the resonance frequencies fr:
It will be possible to enhance the absorption in the very low frequencies, gain a more flat absorption curve, with a designed peak frequency.
Such a system for i.e. noise damping in a hi-press room, could be designed towards the machinery’s frequency of the worst noise level.
A system like this could be built-up by Rockwool Marine Slabs and perforated steel sheeting, placed in the calculated distance.
Where necessary a membrane between the perforated steel and the Rockwool can be fitted, but here great care should be taken not to disturb the ability for the sound energy to pass through the membrane. A foil like aluminium foil glued to the Rockwool will not be the best solution. The membrane has to be an “open” type or a light weight loose foil.
It is also possible to purchase dedicated absorber cassettes complete including bracket system etc from several suppliers. These will of cause also have our non-combustible Rockwool material core.
The same principle is utilised by many ceiling manufactures, again using Rockwool material as the core.
