Rectangular silencers with splitters (baffles) are the basis for many applications related to soundproofing: dissipative silencers, resonators, etc ... . Their total pressure loss (sometimes referred to as back pressure) is a key feature for the design of silencers because it affects in particular the size of soundproofing equipment (and thus: their cost), the sizing of the fan in case of a forced ventilation as well as the energy consumption of the network (e.g. air conditioning circuit, ventilation of equipment premises or of other rooms, ventilation systems for enclosures). In some cases (e.g. aerocondensers soundproofing ), the requirements in terms of total pressure loss are often extreme because it is often needed to consider noise reduction devices generating a total pressure loss being almost zero (i.e. sufficiently low to be neglected).

The total pressure loss must then be taken into account for the design of silencers for which the aerodynamic performance must be optimized by using especially profiled extremities for splitters (baffles).

ITS has integrated the sizing of rectangular silencers made of splitters (baffles) with a low total pressure loss to the simulation software SILDIS (cf. acoustics simulation software).

Calculation routines have been implemented for the calculation of the total pressure loss of those equipments.

Following the modification operationsof the software SILDIS, the comparison of simulation results with bibliographic data (results of measurements, results of calculations by others ...) has shown a satisfactory agreement for numerous combinations of geometrical parameters defining the silencers and for various fluid speeds.

The expected result of improvements to the software SILDIS is an improvement of the accuracy of the sizing of soundproofing equipments such as ventilation silencers and in general: of all industrial silencers of which design is very demanding given the considered flow rates and given the expected performance in terms of aerodynamics often antagonist with the requested acoustic performance in the context of protection of workers, or of preservation of environment, or of improvement of the acoustic comfort in buildings.