Sound pressure level of a Formula 3 car and the influence of detachable muffler-tip

Abstract

This study presents the initial findings associated with the noise emission tests that were carried out in preparation of the UWR Formula 3 car. Even though Formula 3 (F3) race cars are excluded from road vehicle noise emission regulations (EU No. 540/2014), their emission is closely regulated by Fédération Internationale de l'Automobile (FIA) technical regulations. According to FIA regulations, the noise generated by participating cars must not exceed 110 dB (A-weighted) under specific test conditions. The acoustic tests presented in this study were carried out at RAF (Royal Air Force) Cosford airfield in the UK closely simulating FIA recommended conditions. The tests were established to characterise the noise emission of the car during drive-by and stationary conditions. In addition to measuring the Sound Pressure Level (SPL) emitted, the study was extended to evaluating the performance of a detachable muffler tip that is permitted under the FIA regulations. The study found that the tested muffler-tip did not reduce the LAeq acoustic emission under any of the test cases considered. Nevertheless, introducing muffler-tip worsened the LAeq levels by 0.2 dB which is within the standard acoustic measurement uncertainty. Overall, the paper establishes the noise levels associated with F3 cars and the requirement for customised muffler-tips as opposed to aftermarket ones for meaningful noise reduction without adversely affecting performance.