A study of muffler’s factor to reduce noise and conserve engine performance

Abstract

Nowadays, the majority of environment problem is pollution of vehicle including the noise of engine combustion. For this reason, this thesis aims to compare and study the parameters which affect noise reduction on exhaust pipe. Not only reduce the noise pollution, but also maintain the efficiency of the engine. These two substances must be considered. Therefore, the researcher emphasized to study the parameters on 3 types of muffler with an equal volume: direct, reverse and offset type of mufflers. Initiated by data collection, the pressure and the velocity in muffler at the speed of engine at 1000 RPM (slow-running engine mode) and 4000 RPM (maximum running engine mode) were investigated. The data were applied into the program that called “SolidWorks” in order to study parameters. In this step, the relation between the pressure and velocity of exhaust were represented. In addition, the muffler models were selected to manufacture and test by the standard of The Department of Land Transport. As a result, there are two major parameters of the muffler. Firstly, the metamorphism of the exhaust gas flow direction pleasurably causes the lower noise at the speed of engine at 1000 RPM. Besides, an increase of the flow gas distance can diminish noise at the speed of engine at 4000 RPM as well. However this muffler models were tested under the working mode of catalytic device that is standard equipment for automotive vehicles.