Predicting acoustic performance of perforated absorbing silencers, taking into account flow English Free

Engineered to act as soundproofing device, exhaust mufflers have been subject to significant performance improvements with the support, in particular, of absorbing material and perforated elements between internal chambers. Finite Element (FE) method is a good candidate to predict the muffler performance at early stage of the design cycle, taking into account the different physics at stakes. In the presented work, Finite Element based approach has been employed to study the acoustic behavior dissipative mufflers with absorbing material and perforated elements in the presence of mean flow. The effect of non-stationary flow on the acoustic waves’ propagations has been analyzed. Through automated process, a Computational Fluid Dynamics (CFD) simulation solver is used to predict the flow field, which is subsequently imported in a FE model to compute the acoustic performance of the perforated
absorbing muffler. The absorbing material is represented by poro-elastic FE while the perforated elements is represented by FE area isolators with perforation impedance models. Along with validation cases and numerical versus experimental comparisons, the  presented work describes the process for getting, in an time-efficient way, accurate muffler acoustic performance predictions by chaining CFD with FE simulations.