中文摘要：

利用可移动发动机测试台架和便携式排放测试系统，在3个不同海拔高度的地点（青海的望昆、都兰和甘肃兰州）对一台欧III涡轮增压中冷重型柴油发动机进行了实际海拔高度下的燃烧与排放试验，获得了实际海拔环境下的发动机燃烧特性和污染物排放与海拔高度变化的关系．结果表明：随着海拔高度的增加，环境压力减小，相同工况点的最大燃烧压力降低，燃烧始点推迟，预混合燃烧比例增加，燃烧持续期缩短，最高平均温度上升；随着海拔高度的增加，柴油机CO排放增加，在标定转速的中等负荷时有少许降低，而颗粒物排放增加，且在最大转矩转速下尤为明显；但NO2排放的变化规律不明显，随海拔的变化幅度也较小．

英文摘要：

Using a mobile test bench and portable emission measurement system, the combustion and emission characteristics of an Euro III turbocharged heavy duty diesel engine were experimentally investi- gated at three altitudes. The effect of altitude on combustion and emissions of diesel engine was analyzed. Results show that with increasing the altitude, peak combustion pressure is decreased, start of combus- tionis postponed, combustion duration is decreased, and peak combustion temperature is increased. CO emission is increased at higher altitudes, while a certain decrease was observed at middle loads of rated speed. PM emission is increased when altitude is increased, especially at maximum torque speed. Trend of NOx emission was not obvious and its variation is small.