Optimized Design, Analysis, and Validation of a Tractor Muffler for Enhanced Back-Pressure Control and Cost Efficiency

Internal combustion engines generate intense acoustic pulses during combustion, necessitating the use of exhaust mufflers to suppress noise emissions. With evolving regulations on permissible noise levels and the automotive industry's drive toward lightweight, high-performance vehicles, muffler designs must balance effective sound attenuation, minimal back pressure, and reduced mass. This study presents a comparative analysis of three muffler configurations serpentine, rectangular, and zigzag designed using SolidWorks for a light commercial vehicle (LCV) diesel engine. The models were evaluated using computational fluid dynamics (CFD) simulations to assess their acoustic and flow performance. Each design incorporated internal baffle arrangements to enhance sound absorption while aiming to minimize back pressure. The serpentine model featured a perforated baffle layout that promoted multiple reflections and dissipated acoustic energy more efficiently. Simulation results indicated that the serpentine muffler achieved a pressure drop reduction of up to 18% compared to the rectangular model and 12% lower back pressure than the zigzag design under identical engine output conditions. Additionally, the serpentine configuration demonstrated superior sound attenuation in the 200–800 Hz frequency range, which is critical for diesel engine noise suppression. While reducing muffler wall thickness and overall volume contributed to weight savings, these modifications were carefully balanced against the risk of increased back pressure. The optimized serpentine muffler maintained structural integrity and met regulatory noise standards without compromising engine performance. This study highlights that advanced internal geometry, particularly the use of perforated baffles in a serpentine path, is effective for achieving both noise reduction and low back pressure in modern automotive mufflers.