When one is looking to improve the sound attenuation / sound insulation performance of an existing enclosure (acoustic hood) or of an existing wall, ITS offers a wide range of rock wools for all applications related to acoustic insulation / soundproofing related to the protection of workersagainst noise, preservation of acoustic environment, limitation of noise emissions in the energy sector, testing rooms acoustics.
ITS offers rock wool for industrial soundproofing, acoustical insulation, reverberation control in buildings and construction of silencing devices.
At ITS, rock wool is not an interchangeable material, without well-defined technical characteristics, which is difficult to distinguish from glass wool or ceramic fibers, and which can be acquired when you know its price per ton, or - for a given thickness - its price per m2.
It is a well-documented type of porous medium, whose acoustic behavior is known by means of laboratory measurements, allowing the determination of fundamental parameters for acoustic modeling:
- fow resistivity (generally expressed in Nsm-4 or in Pa.s/m2)
- porosity
- tortuosity
- thermal characteristic length (generally expressed in m, or by means of any other unit of length)
- viscous characteristic length (generally expressed in m, or by means of any other unit of length)
This is what a database is available for at ITS, for products of different brands, of different densities, distinguishing the direction normal to the fiber plane and the parallel direction (as is necessary in the case of anisotropic materials i.e. with some properties of which depend on the considered direction).
A rock wool is, based on such parameters, the subject of modeling allowing the evaluation, of physical quantities - depending on the frequency - which are fundamental for the prediction of the acoustic performance of construction products and systems (walls, sound-absorbing linings, silencers):
- the characteristic impedance (generally expressed in Nsm-3 or in Pa.s/m)
- the wave number (related to the propagation constant) generally expressed in rad/m
A rock wool is therefore a material whose characteristics can and must be determined and selected carefully, in line with a performance objective, the prediction of which (often: in the context of a combination with other elements of a multi-layer acoustic structure e.g. porous media, surfacing, perforated protections, plates) constitutes the core of ITS's activity [1] [2] .
[2] cf. Prediction of acoustic performance of plane partitions and walls - software SILDIS® Module 2 / 2+