MTBE和乙醇对汽油燃烧特性的影响

利用同步辐射方法研究了标准样品汽油及其分别添加MTBE、乙醇后的燃烧火焰温度及火焰中多原子物质的种类和浓度.沿火焰高度方向上的芳烃浓度分布说明,MTBE、乙醇有抑制汽油中芳烃氧化的倾向;在样品汽油火焰高度的一半处,没有探测到烷烃物质,而添加MTBE、乙醇后,则探测到多种烷烃物质及其裂解产物.这表明,在燃烧的起始阶段,MTBE、乙醇有抑制烷烃氧化的作用.沿火焰高度方向上的温度分布说明,在燃烧的起始阶段,MTBE、乙醇能够减慢燃烧速度,而当温度升高后,又能加快燃烧速度.

Effect of MTBE and Ethanol on Combustion of Gasoline

With the tunable synchrotron radiation photoionization technique combining with molecular-beam samplingmass spectrometry(MBMS),the intermediates and temperature in the premixed flame were measured.The fuels in testwere standard sample gasoline and gasoline with addition of MTBE or ethanol.The distributions of aromatics in theflame indicate that MTBE and the ethanol have a little negative effect on the oxidation of aromatics.No alkane wasdetected in the middle of the combustion flame of standard sample gasoline,but much alkane could be found whenMTBE or ethanol was added.This fact shows that MTBE and ethanol retard the oxidation of alkane.The profiles ofthe flame temperature show that MTBE and ethanol slow down the combustion at first,and enhance the combustionwhen the flame temperature goes up.