中文摘要：

为了研究生物质燃料含氧量在不同海拔地区对柴油机性能的影响关系，进行了燃用不同氧质量分数的生物柴油，乙醇一柴油（BED）混合燃料和纯柴油的对比试验．结果表明，发动机外特性在不同大气压力下BED混合燃料的转矩均低于纯柴油，并随氧质量分数的增加逐渐降低，随大气压力的升高降幅逐渐减小；当量燃油消耗率在81kPa时均低于纯柴油，随着氧质量分数的增加逐渐降低，随着大气压力的升高，在中低转速下当量燃油消耗率随氧质量分数的增加有上升趋势，在100kPa下超过了纯柴油，负荷特性表明，当量燃油消耗率在不同大气压力下随氧质量分数的增加逐渐降低，降低幅度逐渐增大；随着大气压力的升高，当量燃油消耗率逐渐降低．在81kPa高原环境的低负荷下，各种燃料的碳烟排放差别不大，随着负荷的增大，各种燃料的碳烟排放随着氧质量分数的增加逐渐降低．含氧BED混合燃料的最佳喷油提前角随着混合燃料中生物柴油比例的增加而减小，随着乙醇比例的增加而增大．

英文摘要：

To study the influence of biomass fuel oxygen content on the performance of diesel engine in different altitude regions, the comparative experimental investigations by using the biodiesel-ethanol-diesel （BED in short） blends with different oxygen content and pure diesel were carried out. The test results indi- cate that, at full-load, the torque of engine fueled with BED is lower than that of original engine and it de- creases with increasing oxygen content at different air pressures and the decreasing extent decreases with increasing air pressure. The equivalent specific fuel consumption decreases with increasing oxygen content at 81 kPa. The equivalent specific fuel consumption increases with increasing oxygen content at medium and low speeds when air pressure is increased, and it is higher than that of pure diesel at 100 kPa. The re- suits of load characteristics show that the equivalent specific fuel consumption decreases and the decline extent increases with increasing oxygen content at different air pressures. The equivalent specific fuel con- sumption decreases with increasing air pressure. At low loads of 81 kPa, the difference of soot emission among all fuels is small. With increasing the load, the soot decreases with increasing oxygen content. The optimal fuel injection advance angle of engine fueled with BED fuel retards with increasing bin-diesel comoonent and advances with increasin~ ethanol comoonent.