Predicting sound decay in enclosed spaces remains a topical subject in Research and Development in acoustics.

Enclosed spaces are often an object of study in terms of acoustics when it comes to designing a soundproofing industrial building, an enclosure for a machine/ a process of big size, a test bench, a local for technical equipment or a room intended to house activities such as catering, education, sports and recreation (generally: whenever it is appropriate to consider the impact of reverberation for an indoor acoustical environment).

Acoustic performance of enclosed spaces must be taken into account for the design of premises for which the sound ambiance must be controlled or where the noise impact toward outdoor should be limited.

ITS has integrated the prediction of sound decay in enclosed spaces to the simulation software SILDIS®.

Calculation routines have been implemented for the calculation of temporal sound decay (after noise-off), of reverberation time of premises (rectangular or not).

Following the modification operations of the acoustics calculation software SILDIS®, the comparison of simulation results with bibliographic data (results of measurements, results of calculations by others ...) has shown a satisfactory agreement for the reverberation time of rooms with various dimensions and constructive provisions (in terms of location, absorption and diffusion properties of the absorbing surfaces).

The expected result of improvements to the software SILDIS® (for predicting sound decay in enclosed spaces) is an improvement of the accuracy of the assessment of the impact of reverberation for the definition of soundproofing equipment such as absorbent wall panels, suspended absorbing ceilings, suspended absorbent baffles, noise shields and in general: of all soundproofing devices for rooms in which the design is very demanding given the sound power levels of noise sources considered (inside the room) and/or the expected performance in terms of acoustics in the context of protection of workers, or of preservation of environment, or of improvement of the acoustic comfort in buildings.