Simulation of Cylindrical Resonator with Spiral Neck and Straight Neck to Attenuate the Low Frequency Noise of Muffler

Abstract

This paper is concentrated for improving the transmission loss and reduces the low frequency noise level by development of Helmholtz Resonator within a limited space. The modified Helmholtz resonator, i.e. cylindrical resonator with spiral neck is used to occupy the small space. Introduction of spiral neck instead of straight neck with cylindrical cavity reduces the space of resonator. For first cut-off frequency (resonance frequency) the volume of resonator is fixed, so with the help of spiral neck its length increases, volume increases and its curvature effect is also helpful in the reduction of noise. The finite element analysis tool Comsol multiphysics is used to validate the result. The results shows interesting factor that resonator not only attenuate a particular low frequency noise as well it increases transmission loss with spiral neck. Helmholtz resonator with a spiral neck can achieve high sound reduction within a small space at low frequency.