CFD simulation analysis of a rectangular chambered muffler model for a C.I. engine

A compression ignition (CI) engine can produce significant pressures and temperatures in its combustion chamber. The exhaust system’s outlet is the atmosphere so that a conventional silencer can investigate pressure wave attenuation. As a result of an adverse pressure gradient, the exhaust system may not function properly. For computational fluid dynamics simulations, hot exhaust gas can be selected from muffler pipes exiting engine exhaust systems. This study examines a Mahindra Maximo C.I. engine’s rectangular chambered muffler model. In the design of one of the two mufflers considered, the inlet, outlet, and center pipes are perforated, which may result in better, more efficient noise reduction. CFD analysis results are used to establish the pressure distribution used in both muffler models to compute transmission loss. Ansys Fluent 2022 R2 is used in this study to compare two reactive-type muffler designs, one without perforations and one with perforations, and Fusion 360 (V.2.0.13168) software is used to design reactive-type mufflers. It was found that the perforated muffler model exhibits a higher transmission loss than the non-perforated muffler model, thereby establishing its superiority over the non-perforated muffler model. Static pressure and transmission loss are proportional in the rectangular chamber muffler model, with a 1.56% increase in static pressure corresponding to a 25% increase in transmission loss.