| The research process of improving performance and reducing the emission of YC4112ZLQ turbocharged intercooler four valves diesel engine was introduced to meet the requirement of Euro- II regulations. In order to meet more strict emissions regulations to improve performance and to reduce emissions, many countries' manufacturers and research institute were absorbed in the application of four valves from gasoline engine to diesel engine. The meaning of the research process is to put four valves technology into YC4112ZLQ diesel engine to meet the emissions regulation of nation.The research used the method of combining theoretic calculation and experimental research. First, calculated theoretically. Second, did some experiments. The main method of improving performance and reducing emission is to optimize the swirl ratio of four valves head. Improvements of intake and exhaust system include turbocharged system matched, local camshaft optimized, application of pulse exhaust pipe, adjustment of intake temperature and pressure etc. Improvements of combustion system include improvement of compression ratio, swirl ratio matched, adjustment of nozzle tip protrusion etc. Improvements of fuel injection system include application of 7 holes nozzle, adjustment of injection advance degree etc. Furthermore researched the reducing the oil consumption rate. Experiments proved that matched and optimized these systems, the performances and emissions were improved observably. Meantime compared with the original engine, NOx was 14% lower, PM was 4% lower, HC was 20.8% lower, CO was 16.7% lower. In the research process, AVL670 combustion analyzer and Germany FEVemission test system were used to test and compare the different important plans. In the thesis, research all kinds of projects carefully.By working hardly, YC4112ZLQ turbocharged intercooler four valves diesel engine met requirements of performance and Euro- II emission regulation. |
