Modulation of sound propagated from the inlet duct of an automotiveturbocharger compressor, using various porous materials

Sound absorptive materials have been widely utilized to control, manipulate, and mitigate the propagation ofsound waves in the aerospace and automotive industries. This paper proposes that porous materials can befitted as the coating liner to the inlet duct of the turbocharger compressor in order to absorb the incidentexcitation and hence, reduce the propagation of sound waves. As a result, three different types of absorptivematerials are used as coating liners to determine the impact that varying material properties have on theacoustic absorption performance of the system. A finite element approach is conducted, and acoustic pressureand poroacoustics studies are carried out over the desired frequency range (۱-۲۰ kHz) using COMSOLMultiphysics. Sound transmission loss (TL) and sound pressure level (SPL) are investigated for the modelswith and without liners. The results indicate that sound-absorbing materials can be employed to significantlydiminish sound levels in the turbocharger compressor inlet duct. According to the results, absorptive linerswould considerably increase the maximum TL and lessen the sharp drop in TL that appeared in the modelwithout liners at around ۴۳۲۱Hz. In addition, the average TL has increased due to the replacement of valleyswith peaks. By adding only ۵mm of an absorptive liner, the average TL was increased by ۳.۳%. The presentstudy intends to introduce a fundamental approach that can be applied to many promising fields such asaerospace and automotive engineering.

Keywords:

Porous materials , Sound-absorbing , sound transmission loss , turbocharger compressors , noiseand vibration attenuation