柴油机生物柴油-甲醇混合燃料燃烧与排放特性

Combustion and emission characteristics of blended fuel of biodiesel and methanol for diesel engine

分别在100mL生物柴油(M0燃料)中添加10mL甲醇、20mL甲醇与12mL油酸,经过相关处理后形成新的微乳化燃料M10燃料与M20燃料。以台架试验与排放分析法为基础,当发动机转速点为1 500r/min、平均有效压力分别为0.088 9、0.177 0、0.266 0、0.354 0、0.443 0、0.531 0MPa时,分别对3种燃料的燃烧特性与排放特性进行了试验研究。试验结果表明:与M0燃料相比,M10燃料与M20燃料的滞燃期延长,燃烧持续期缩短,3种燃料的最大滞燃期分别为6°、7°、8°;M10燃料与M20燃料的峰值压力、峰值压力升高率以及峰值燃烧放热率均增大,3种燃料的最大峰值压力升高率分别为1.236、1.377、1.280MPa/(°),3种燃料的最大峰值燃烧放热率分别为0.280、0.281、0.297kJ/(°);M10燃料与M20燃料的HC、CO与碳烟排放均降低;NOx排放没有明显变化。

10 mL methanol,20 mL methanol and 12 mL oleic were added into 100 mL biodiesel（M0 fuel） respectively,and M10 and M20 micro-emulsified fuels were developed after processing.Based on the bench experiment and emission analysis,when the engine speed was 1 500 r/min and the average effective pressures were 0.088 9,0.177 0,0.266 0,0.354 0,0.443 0 and 0.5310 MPa respectively,the experiments for combustion and emission characteristics of those three fuels were carried out.Experiment results show that compared with M0,the combustion delay periods of M10 and M20 are longer,the combustion durations are shorter,and the maximum combustion delay periods of those three fuels are 6°,7° and 8° respectively.The peak pressures,the increasing rates of peak pressures and the exothermic rates of peak combustions for M10 and M20 increase,the maximum increasing rates of peak pressures for those three fuels are 1.236,1.377 and 1.280 MPa/（°） respectively,and the maximum exothermic rates of peak combustions for those three fuels are 0.280,0.281 and 0.297 kJ/（°） respectively.The HC emissions,CO emissions,smoke intensity emissions of M10 and M20 decrease,but there are no significant change of the NOx emissions of M10 and M20.