基于进排气海拔模拟发动机台架，针对国六柴油机开展了0~4 000 m海拔的WHTC排放循环测试，并将WHTC循环拆分为整车实际运行中的常用工况（城市工况、郊区工况、高速工况），探讨了不同海拔、运行工况、海拔与运行工况共同作用下的柴油机污染物排放特性。结果显示：4 000 m海拔下CO，HC，NO_x排放较0 m海拔分别增加了11.5倍、25.3倍、6.4倍，而尾排PN比排放几乎不受海拔的影响；城市工况CO，HC，NO_x比排放分别是高速工况的7.7倍、5.5倍、6倍，郊区工况PN比排放分别是城市工况和高速工况的7.5倍和3.4倍；柴油机尾排气态污染物排放与整机输出功率及海拔强相关，CO，HC，NO_x比排放与海拔系数和功率系数比值的相关系数分别为0.91，0.78，0.79，而PN比排放与整机输出功率及海拔的相关系数均较低。

Based on an engine test bench with intake and exhaust altitude simulation function, the world harmonized transient cycle（WHTC） emission tests were carried out on a China Ⅵ diesel engine at altitudes ranging from 0 m to 4 000 m. The WHTC cycle was further divided into typical operating conditions corresponding to the actual vehicle operation scenarios, namely urban condition, suburban condition and highway condition. The pollutant emission characteristics of diesel engine were investigated under different altitudes and operating conditions, as well as the both combination. The results showed that the emissions of CO, HC and NO_x at 4 000 m increased by 11.5 times, 25.3 times and 6.4 times respectively compared with those at 0 m, while the exhaust particle number（PN） specific emission was almost unaffected by altitude. The specific emissions of CO, HC and NO_x under urban condition were 7.7 times, 5.5 times and 6 times of those under highway condition respectively; and the PN specific emission under suburban condition was 7.5 times and 3.4 times of that under urban condition and highway condition respectively. The exhaust gaseous pollutant emissions of diesel engine were strongly correlated with the engine output power and altitude. The correlation coefficients between the specific emissions of CO, HC, NO_x and the ratio of altitude coefficient to power coefficient were 0.91, 0.78 and 0.79 respectively, whereas the PN specific emission exhibited low correlation coefficients with both engine output power and altitude.