为研究生物柴油-乙醇-柴油(简称BED)混合燃料对高原地区发动机的性能影响,在不同环境下进行了BED混合燃料的相溶性和稳定性测试的基础上,在高原环境下进行了高压共轨柴油机燃用纯柴油和6组不同比例BED混合燃料的台架试验。结果表明,生物柴油、乙醇和柴油可在一定温度范围内按照不同比例配制成稳定的混合燃料,但其稳定性随温度降低而变差。当喷入气缸内燃料体积不变时,与燃用纯柴油相比,燃用BED混合燃料发动机的动力性下降;经济性有所改善,高速时改善效果更为明显;碳烟排放下降,高负荷时比低负荷时下降幅度更大。BED混合燃料的最佳喷油提前角随生物柴油比例的增加而减小,随乙醇比例的增加而增大。
In order to investigate the effects of biodiesel-ethanol-diesel(BED) blend fuel on the performance of diesel engine in plateau area, on the base of measurements on the stability and compatibility of BED blend fuel at different temperatures, a bench test on a high-pressure common rail diesel engine fueled with pure diesel fuel and six BED blend fuels in different proportion is carried out under a plateau environment. The results show that biodie- sel, ethanol and diesel can be mixed together with different proportions in a certain range of temperatures to form a stable blend fuel with its stability worsens as the temperature fails. Compared with pure diesel fuel with the same volume of fuel injected into cyhnder, the power of engine fueled with BED fuels lowers while its fuel economy im- proves, especially at high speed, and the soot emission reduces, in particular at high load. The optimal fuel injec- tion advance angle for BED fuel reduces with the rise in biodiesel proportion and increases as more ethanol added.