【作者】 刘津；

【导师】 祁东辉；

【作者基本信息】 长安大学 ， 载运工具运用工程， 2008， 硕士

【摘要】 生物柴油是由植物油或动物脂肪通过酯交换反应而得到的脂肪酸甲酯或乙酯,具有与石化柴油十分相似的理化特性,并且由于生物柴油无毒,可生物降解和再生,同时也可以减少柴油机的有害排放物,因此生物柴油是一种绿色、清洁的替代燃料,它以其良好的环境效益受到越来越多的关注。本文在充分认识生物柴油在柴油机上的应用方法、生物柴油的制取及其理化特性的基础上,对生物柴油及其与柴油的混合燃料的使用性能进行了试验研究,进一步了解生物柴油对柴油机的燃烧特性、动力性、经济性以及排放特性等方面的影响。研究结果表明:与燃用柴油相比,发动机燃用生物柴油时的转矩和功率略有下降;有效燃油消耗率有所增加;有效能量消耗率在低转速小负荷时略有增加,在其他工况运行时与柴油机基本相当。发动机燃用生物柴油和各掺混比生物柴油/柴油混合燃料时,能有效减少HC、CO和碳烟排放,但NOX排放略有增加。与原柴油机相比,发动机燃用生物柴油时,在所有工况下,滞燃期缩短,最高爆发压力增大;最大压力升高率在中小负荷时略有增加,在大负荷时减小,压力升高率峰值对应的曲轴转角略有提前;最大瞬时燃烧放热率在中小负荷时略有增大,在大负荷时略有减小,瞬时燃烧放热率峰值对应的曲轴转角提前;燃烧持续期在低转速小负荷时略有延长,在高转速大负荷时略有缩短。在不改变发动机结构的情况下,生物柴油可以和柴油以任意比例混合而不会对发动机的性能产生明显的影响。更多还原

【Abstract】 Biodiesel is mainly composed by fatty acid-first ester and second ester, which is produced from vegetable oils or animal fats through the transesterification reaction. Its physical and chemical characteristics are similar with diesel. Because biodiesel is non-toxic, biodegradable and renewable, and can also reduce the harmful emissions from diesel engines, so it is a green and clean alternative fuel, and it attracts people’s attention for its good environmental benefits gradually.Based on deeply understanding to the application of methods, the biodiesel’s produce process and its physical and chemical characteristics, this paper studied the using performance of biodiesel and the concoction of biodiesel/diesel, and learned more about that biodiesel has the impact on diesel engine’s combustion, dynamic, economy and emission characteristics.The results show that: Compared with the diesel, when the diesel engine fueled with pure biodiesel, the torque and power decreased slightly, the effective specific fuel consumption increased, the effective specific energy consumption increased slightly in low-speed small load, it had the similar with the diesel engine in other situations. When the engine fueled with biodiesel and the concoction of biodiesel/diesel, HC, CO and soot emissions reduced effectively, but NOX increased slightly. Compared with the original diesel engine, when engine burning biodiesel, the ignition delay period was shortened and the maximum eruptive pressure increased in all conditions. The maximum pressure increased in small and medium-sized load and decreased slightly in heavy load, the crank angle of the maximum pressure was ahead of schedule slightly. The highest rate of hest release increased in small and medium-sized load and decreased slightly in heavy load, the crank angle of the highest rate of hest release was ahead of schedule slightly. The combustion duration was extended slight in low-speed small load, was shortened slightly the high-speed large load. Without changing in the structure of the engine, diesel and biodiesel can be mixed in any proportion and the performance of the engine will not have a significant impact.更多还原