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With the development of automobile industry, our society faced with increasingly serious tensions and environmental problems of oil. Development of friendly energy-saving and new energy vehicles is important to achieve sustainable development strategy for automotive industry. Meanwhile, natural gas fuel for its good characteristics and rich reserves of the world recognized as one of the new energy automotive quality.Based on the technology experience of natural gas engines in China and abroad, we combined with CNHTC project. Our team undertake "dedicated natural gas engine development" in the sub-topics to WT615.95 series models based on natural gas engine research and development. Research group which I take part in selection gas control system integration match the optimal design of critical components, and engine electronic control calibration, combined with other research research group together to complete the project.This paper reviews the background of the topic, natural gas vehicle development process, the development of the domestic natural gas engines and technical characteristics of the technical routes. We analyzed the natural gas engine technology at home and abroad,and based on the proposed Task Force to meet the national IV emission electric gas engine development program; to WT615.95 natural gas engine-based models, the use of lean-burn, turbocharged and intercooled, low eddy current combustion system, single-cylinder high-energy independent of the ignition, electric fuel pressure regulator closed-loop control and oxidized catalysts.These technical route could improve the dynamic performance of natural gas engines and play their emissions and economic advantages.Secondly, in the text of the key components of gas electric control system performance matching and optimization of fuel control program (electronically controlled mechanical mixer surge) were studied on the mixer design different type of line to accommodate the spool different gas composition fuel.The methane of fuel is 40%,60%,95%. Then we used the FLUENT simulation software, combined with modified boundary conditions and experimental validation, have designd a good effect of the spool-type line.Besides, we used the different ignition energy 25mJ,35mJ,45mJ,65mJto stufe the engine power, external characteristic economy, emissions performance and fire boundaries.The condition of fire boundaries is at rated speed 2200rpm, the high-speed 1800rpm,1300rpm and maximum torque low-speed 900rpm.To conclude, the effects of ignition energy on the power draw different, external economy and emissions characteristics not significantly different.But the high ignition energy can not only expand the boundaries of the fire, but also affect the life of spark plugs.Our team finally considered various factors, choosing the best ignition energy 45 mJ.Last, to meet through participation StateⅣemission engine calibration, the calibration methods are explored to make the engine work better in various conditions, such as the concentration of the ignition advance angle and the calibration of the orthogonal test method and boost pressure calibration.In this paper, natural gas engine control system to match the basic method and calibration procedures can be alternative fuel engines for the future research to provide a reference.
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