Performance Optimization For Exhaustmuffler With Catalytic Converter

With the implementation of the newest motorcycle EmissionⅢ，the Emission andnoise control standard has became much stricter. In order to meet the requirement ofthe Emission Ⅲ, enterprises have tried to find more new technologies and methods,including taking measures conducted in-engine and out-engine cleaning technologies.Catalyst, as the core part of Exhaust System has developed well. Considering thestructure character of exhaust system and catalyst, the catalyst is always fixed with themuffler to be one part, which is the muffler with catalytic converter, and it brings thenew requirement for the optimization of the position of the catalytic converter.Based on the project that optimize exhaust system to meet the requirement of theEmission Ⅲ, the effect of Installment the catalytic converter to acoustics performanceand aerodynamics performance of the muffler is analyzed. Combined with thetechnology of reducing emission, the position of the catalytic converter is optimized.This paper base on the test parameters and the structure size of engine, model ofengine is established with GT-Power，and the simulation results is exact throughcompared with test results. While the model of muffler with catalytic converter isestablished with GT-Power, and coupling the engine model. Insertion loss and pressureloss of the exhaust muffler with catalytic converter is analyzed. According to thecalculating results, improvement on muffler structure is conducted. The insertion lossincreases3～5dB after improvement, the pressure increases also, but the effect topower of engine is little.From the whole, this article does some research about establishment andsimulation of motorcycle engine, analysis and improvement of muffler with catalytic,which gives some ideas of the design.