Design and simulation of an exhaust muffler for a single cylinder diesel engine for the Wuzheng tricycle model 7YPJ-1750PD

Abstract

Exhaust muffler systems are mechanical devices used to absorb and attenuate the noise level of exhaust gases as they enter the atmosphere. This work was aimed at designing and simulating the performance of an exhaust muffler system for the Wuzheng tricycle model 7YPJ-1750PD using its simple expansion chamber as a benchmark to lower the engine exhaust noise by minimising the backpressure. A combination muffler was designed alongside a simple expansion chamber. The two were assembled using solid Edge CAD software. The system was made to undergo CFD and harmonic acoustic simulations using the ANSYS FLUENT software to check its working conditions and performances. It was observed that the assembled muffler system reduced the noise level of the original muffler by 15 dB with a minimal effect on the engine. The assembled muffler system also had a lower average backpressure (911.3 Pa) as compared to that of the original muffler (1151.6 Pa).  From the simulation results, the combination muffler was found to be more efficient in attenuating engine exhaust noise levels as compared to the original muffler.