Design of a Reactive-Style Muffler for a Formula SAE Race Car

The noise generated by internal combustion engines, particularly in high-performance vehicles like Formula SAE race cars, presents a significant challenge in adhering to strict competition noise regulations. To address this issue, mufflers are essential for reducing acoustic emissions. This study focuses on the design, manufacturability, optimization, and validation of a reactive-style muffler specifically for a Formula SAE combustion competition car. The proposed muffler utilizes two chambers to generate destructive interference, targeting the two dominant exhaust frequencies of the Honda CBR600RR engine to maximize transmission loss and reduce noise levels below the SAE-mandated range of 103–110 dB(C). A 3D model of the muffler was developed using SolidWorks, capturing the precise geometries required for acoustic optimization. The exhaust noise and muffler performance were simulated using GT-Suite, allowing for an evaluation of noise attenuation across engine speeds. Experimental testing was conducted to validate the GT-Suite model and assess the muffler’s effectiveness in real-world conditions. This testing involved measuring noise levels with a microphone, both with and without the designed muffler, and comparing it to an aftermarket absorption muffler. The results showed that, for the Formula SAE combustion competition, the reactive muffler design with two chambers achieved superior noise reduction compared to the absorption muffler, confirming the effectiveness of destructive interference in attenuating noise. The study demonstrates the feasibility of using a combination of SolidWorks and GT-Suite for designing and optimizing mufflers, as well as validating the results through experimental testing. These findings provide a framework for future improvements in exhaust noise reduction for Formula SAE vehicles, balancing both noise control and engine performance.