生物制气—柴油双燃料发动机燃烧特性和放热规律研究

【作者】 刘乔明；

【导师】 罗福强；

【作者基本信息】 江苏大学 ， 动力机械及工程， 2005， 硕士

【摘要】 生物制气是一种优良的发动机替代燃料,是解决能源短缺的重要途径之一。生物制气在我国具有一定的使用规模和发展水平,在发动机上具有广阔的应用空间。由此,笔者介绍了生物制气的两种制取方式,阐述了生物制气的热化学属性和在发动机上的应用状况,介绍了生物制气发动机的动力特性和排放状况,对生物制气发动机的性能和各项指标进行了综合评价。 通过改装ZH1115直喷柴油机为双燃料发动机,由柴油引燃,燃用生物制气来推动发动机运转,测量了发动机在不同转速、负荷以及供油提前角改变的情况下气缸压力数据,计算分析了发动机的燃烧特性和放热规律状况,比较了原机和双燃料发动机的差别。 测量分析结果表明:双燃料发动机与燃用纯柴油时的发动机相比,燃烧始点较迟,在低速大负荷时比柴油机气缸最高燃烧压力及最大压力升高率要大,在其余工况比柴油机要低。双燃料发动机着火始点较柴油机迟,但最大放热率较柴油机大,后燃较严重。双燃料发动机在转速不变负荷增加时,燃烧始点相对提前,滞燃期缩短,最大放热率及温度提高,对应的曲轴转角提前,后燃增加。供油提前角提前,负荷及转速对放热规律的影响效果是相同的,但燃烧始点、燃烧终点、最大放热率等所对应的曲轴转角也相应提前。更多还原

【Abstract】 Biogas is a kind of good alternative fuel for the engine. It is one of the most important way to solve the shortage of energy. In our country the biogas is used more and more widely and developed constantly. Two kinds of method to produce biogas are introduced, the thermochemistry of biogas and its influence on the power and emission of biogas engine are discussed.Based on the measured cylinder pressure at different engine speeds, loads and the fuel supply advance angles, the combustion characteristics and heat release rate of a biogas diesel dual-fuel engine are calculated and analyzed. The differences of these characteristics between a biogas diesel dual-fuel engine and the diesel engine are compared and analyzed.It is found that the cylinder pressure and maximum pressure rise of the biogas diesel dual-fuel engine are lower than that of the diesel engine except when the engine speed is low and load is high. The ignition time of the biogas diesel duel-fuel engine is retarded than that of the diesel engine, but the maximum heat release rate and the after combustion period of the biogas diesel duel-fuel engine are larger than that of the diesel engine. When the load of the biogas diesel duel-fuel engine increases but the engine speed is at the same, its ignition time is advanced, its ignition delay period is shorter, its maximum heat release rate and temperature are larger. The changing tendency of the combustion characteristics of the engine according to the engine speed and load is the same when the fuel supply advance angel changed.更多还原