Effect of Variation in Build-Up Parameters on Noise Reduction in Automobile Engine Silencers

Abstract

The study focused on practical methods of reducing noise levels in automobile engine silencers. A comprehensive step to examine the flow pattern in relation to noise level generation, modify silencer parameters to effect noise level reduction is considered. The experimentation commenced with flow linearization process and this was followed by a design/build/test laboratory procedure to ascertain the minimum noise level achievable by varying the inlet pipe size, resonating chamber length and the orifice size of the geometric build up of the silencers. Results from experimentation shows a reduction in noise level to the tune of 13.2 dB (A) when comparison is made with the initial noise level of silencer used as the baseline level at 76.9 dB (A). The results was incorporated to generate an optimum model for the IC-engine (Volkswagen Passat Model) of 1921 cm3 engine capacity used as the test engine during the experimentation. Noise level in dB (A) were depicted on noise level-time graph.