Search Results

Motorcycle exhaust mufflers are important devices which influence not only exhaust noise and engine performance but also appearance of motorcycle. Since the improvement of engine performance often contradicts the attenuation of exhaust noise in designing mufflers, it is necessary that both the exhaust noise and the engine performance are predicted simultaneously. Recently, unsteady-state one-dimensional computational fluid dynamics (1-D CFD) analysis is being applied to this problem. We have developed the technique to predict engine performance and exhaust pulsating sound by adopting unsteady-sate 1-D CFD analysis (here, we treat the exhaust pulsating sound which is a discrete frequency component of exhaust noise). In this paper, firstly, as a result of a preliminary study, it is shown that our prediction technique can predict the acoustic transmission loss of a muffler.