Numerical Predictions for Can Type Muffler of a Motorcycle

To attain high performance and low emission at the same time, computational fluid dynamics was incorporated into a design optimization stage of the muffler. Splitters were equipped at the short bend just upstream of the catalyst to suppress flow separation and mal-distribution within the catalyst region. Design screening had been done for the splitters based on result from the steady states CFD. Then the unsteady CFD for the selected splitter design showed uniform flow field within the catalyst region even when the flow rate was abruptly changed due to intermittent exhaust process.