Optimization of internal geometry for maximum transmission loss in a reactive muffler

Noise pollution from internal combustion engines in vehicles and industrial equipment poses an environmental challenge. Exhaust systems use mufflers to reduce noise by attenuating sound waves. This study focuses on optimizing the extended inlet length and diameter in a reactive muffler with a single expansion chamber and extended sections. The aim is to enhance transmission loss in a targeted frequency range for better noise reduction. Using the Taguchi Method, the study identified optimal design parameters for sound attenuation. Acoustic performance was assessed through two methods: (1) numerical simulations using COMSOL Multiphysics and the Finite Element Method (FEM) to analyze sound wave behavior, and (2) experimental validation via the two-load method to measure transmission loss in a prototype. Results highlight key design insights for optimizing reactive mufflers, offering a robust framework for achieving superior noise control in applications requiring frequency-specific attenuation.