Study Of Low-cost Out-engine Purification System To Meet The Emission Standard (CHN Stage Ⅲ) For Motorcycles

It is self-evident for the importance of controlling the vehicle exhaust pollution in the background of energy-saving and emission-reduction.The motorcycle had been a major component of China's vehicle fleet whose exhaust pollution has increasingly become a serious social nuisance, made widespread concern in all sectors of society.July 1,2010,China has been implementation of GB14622-2007, that is motorcycle emission limits and measurement methods (method conditions, the Chinese StageⅢ),to further reduce motorcycle emissions pollution,therefore, it has become an urgent task for the motorcycle emission standards to meet the requirements of the countryⅢstandard in period of time.This study is launched in this context and comes from a part of the research task of Guangdong Provincial Science and Technology Project "key technology of motorcycle energy saving (item number:2010B0109000015) ".What the work is to develop a low-cost emission control system by a carbureted prototype motorcycle (HB125) of FuXing company in Guangdong.Two-level of catalysts were taken to deal with cold-start emissions and missions of pollutants in other conditions. Specifically:First,to adjust the fine on the carburetor is to improve emissions performance of the initial prototype; Second,to choose the first class and the main catalyst oxidation catalyst to suit the prototype by a means of the experiment, and to determine their Installation location under the exhaust pipe temperature.Third,to design the main catalyst of the shell structure with CFD methods;Fourth,to select the secondary qi design based on the experimental test. System design solutions can be summarized as "fine-tuning the carburetor+levels added to the secondary air catalytic converter agent. "The results show that:mixture air-fuel ratio after fine-tuning the carburetor can be controlled in the range of 12.8≤α≤13.5, CO emissions decreased 41.59%, HC emissions decreased 16.82%, fuel economy increase of about 0.57%, the maximum power the engine decreased 1.12%, which preliminary reaches the expected effect. State LawⅢworking conditions results show that:the new test about vehicleCO, HC and NOx emissions are 1.22g/km,0.19g/km and 0.13g/km. After aging 100h bench test, CO, HC and NOx emissions are:1.41g/km,0.12g/km and 0.21g/km, can fully meet the requirements of the country III and purification capacity greater redundancy. Therefore, the design for low-cost exhaust gas after treatment system is appropriate, can make kind of car emission standards.