【作者】 李远；

【导师】 张兆合；

【作者基本信息】 哈尔滨工业大学 ， 车辆工程， 2011， 硕士

【摘要】 伴随着人类对新能源的渴求,代用燃料将成为内燃机的燃料来源,燃料的理化特性决定了内燃机更换燃料必须对压缩比、空燃比及点火提前角等进行优化匹配。用传统试验方法匹配,周期长、费用高。本文以HH465QE1汽油机更换压缩天然气、氢气和乙醇燃料为研究对象,以性能为研究目标,利用GT-POWER内燃机仿真软件,确定不同燃料的压缩比,计算空燃比和点火提前角基础MAP。本研究建立了HH465QE1汽油机的仿真计算模型,通过仿真计算,所建的内燃机模型与原型机相比最大功率上升了1.9%,最大转矩下降了2.4%,最低油耗降低了0.5%,仿真结果与原机数据基本符合。由于天然气和氢气体积低热值小,标况下动力性能比较差,对其采取增压的方式进行了仿真计算,天然气和氢气的进气压力分别为0.15MPa、0.3MPa。通过比较不同压缩比下代用燃料内燃机的有效功率、有效燃料消耗率,根据内燃机设计时压力升高率和气缸压力的要求,选取压缩天然气内燃机的压缩比为14,氢气内燃机的压缩比为13,乙醇内燃机的压缩比为11。分析了压缩比随负荷、转速变化的可变压缩比的优势。对设定典型工况下过量空气系数在0.8-1.1范围内的空燃比动力性和经济性进行了仿真计算。提出了在低负荷、中小负荷、大负荷时,代用燃料内燃机空燃比的设定方案;得到了设定工况下的H₂内燃机空燃比MAP。采用先广泛后精确的方法,依据动力性和经济性输出,确定代用燃料内燃机的最佳点火提前角。根据每种代用燃料54种工况下的点火提前角,绘制了点火提前角MAP图,就整体趋势而言,仿真计算的点火提前角符合转速、负荷对点火提前角的影响规律。通过比较三种燃料的点火提前角,其大小还与燃料本身的燃烧速度有关。更多还原

【Abstract】 Alternative fuel will become internal combustion engine fuel sources because of human desire,replacement fuel physic-chemical properties decide that internal combustion engine must optimize compression ratio, air/fuel ratio and advanced ignition Angle. But,the traditional test methods match long period and high cost. Based on HH465QE1 gasoline internal combustion engine replacement compressed natural gas, hydrogen and ethanol fuel as research object, by performance as the research target, use GT - POWER internal combustion engine simulation software, different fuel compression ratio is defined, air-fuel ratio and advanced ignition Angle basic MAP is calculated.HH465QE1 gasoline internal combustion engine simulation calculation model is established, through the simulation calculation, internal combustion engine prototype is rose 1.9% compared the maximum power, the maximum torque is dropped 2.4%, minimum fuel consumption is decreased 0.5%, the simulation results with the original machine basic data.Because the natural gas and hydrogen volume low calorific value of small, standard condition dynamic performance is poorer, the way to adopt a pressurization simulated computation, natural gas and hydrogen respectively the inlet pressure 0.15 MPa, 0.3 MPa. By comparing different compression ratio of internal-combustion internal combustion engine alternative fuel effective power, efficient fuel consumption, according to internal combustion internal combustion engine design pressure increase rate and the cylinder pressure requirements, the selection of compressed natural gas compression ratio of internal-combustion internal combustion engine for 14, hydrogen compression ratio of internal-combustion internal combustion engine for 13, ethanol compression ratio for 11. Analysis the compression ratio after load, speed variations of variable the advantage of compression ratio.Typical working conditions for setting in excess air coefficient 0.8-1.1, within the scope of the performance and fuel economy of air-fuel ratio is simulated calculation. Alternative fuel of air-fuel ratio setting scheme is put forward in low load, small and medium-sized load, large load of internal combustion engine; And get a set of H₂ internal combustion engine under the conditions of air-fuel ratio MAP.After the first widely accurate method, based on the performance and fuel economy of output, make sure the best alternative fuel combustion engine ignition timing. According to each alternative fuel of 54 cases of advanced ignition Angle, painted ignition timing the MAP figure, as a whole, the trend is concerned, simulation ignition timing accord with speed, load to advanced ignition Angle of the influence law. Through comparing three fuel ignition timing, the size also and fuel combustion rate itself concerned.更多还原