大豆毛油制备生物柴油在发动机上的应用

Application of biodiesel from soybean crude oil into an engine

为了研究大豆毛油制备生物柴油对直喷式柴油机性能的影响,测试了生物柴油的主要理化特性指标,通过发动机台架试验,对比分析了不同体积分数生物柴油/柴油混合燃料发动机的动力性、经济性和排放特性,探讨了生物柴油对发动机性能的影响机理。研究结果表明:生物柴油的粘度、闪点和酸值明显高于柴油,密度和凝点略高于柴油,但热值和冷滤点略低于柴油;生物柴油/柴油混合燃料发动机的动力性与柴油机相比有所降低,有效燃油消耗率有所升高,有效能量消耗率与柴油机相差不明显。在外特性工况运行,柴油发动机的CO、HC和碳烟排放明显高于混合燃料发动机,而NOx排放略低;在中、小负荷工况,柴油发动机的CO和碳烟排放与混合燃料发动机相差不明显,在大负荷工况则有明显升高;在整个负荷范围内生物柴油的HC排放低于柴油,而NOx排放略有升高。

In order to study the effect of biodiesel from soybean crude oil on the performance of di-rect injection diesel engine, the physical and chemical properties of biodiesel were tested. The power performance, fuel economy and exhaust emission of biodiesel/diesel blended fuel with dif-ferent biodiesel volume fraction were analyzed and compared, and the influence mechanism of biodiesel on engine performance was studied. The results show that the viscosity, flash point and acid value of biodiesel are evidently higher than those of diesel, the specific gravity and solidifying point are slightly higher, but the heating value and cold filter clogging temperature are slightly lower. Compared with diesel engine, the power performance of biodiesel/diesel blended fuel en-gine is slightly lower, the specific fuel consumption is higher and the specific energy consumption is al-most the same. Under speed characteristics of full load, CO, HC and smoke emission of diesel are evi-dently higher than those of blended fuels, but NOr emission is slightly lower. Under middle and low en- gine load, CO and smoke emission of diesel are almost the same as those of blended fuels, but evidently higher under high engine load. Under all range of engine loads, HC emission of biodiesel is lower than that of diesel, but NOr emission is slightly higher. 1 tab, 14 figs, 10 refs.