Abstract: In order to analyze the emission characteristics of various pollutants under the condition of cold-start of heavy-duty diesel vehicles, 5 heavy-duty diesel vehicles were selected for actual road vehicle testing. The test results show that, NOX accounts for a relatively large share in the cold start phase, while CO and PN account for a relatively small share in the cold-start phase, from the perspective of cumulative emissions. The specific emissions of NOX and CO during the cold start phase are relatively large, from the perspective of specific emissions. However, the specific emission of PN during the cold start phase was not always the larger one. Comparing the changes in the concentration of various pollutants before and after the cold start, it is found that NOX has a clear downward trend before and after the cold start, while the change trend of PN and CO is not obvious, indicating that the situation of the vehicle itself play a role in the emission of the PN and CO. It should be paid more attention to the NOX and CO emissions of vehicles during the cold start phase in the future.

Key words: Cold-start phase; PEMS; Heavy-duty diesel vehicles; Pollutants emission

摘要： 为了分析重型柴油车冷启动情况下各污染物的排放特征，文章选取了 5 辆重型柴油车进行实际道路车载试 验。试验结果表明，从累计排放量上看，NOX 在冷启动阶段的占比较大，而 CO 和 PN 在冷启动阶段的占比较小； 从比排放上看，冷启动阶段 NOX 和 CO 的比排放较大，而 PN 在冷启动阶段的比排放时大时小；比较冷启动前后各 污染物浓度的变化，发现 NOX在冷启动前后有很明显的下降趋势，而 PN 和 CO 的变化趋势不明显，与车辆自身的 情况有较大关系。车辆在冷启动阶段的 NOX 和 CO 排放是未来需要关注的重点。

关键词: 冷启动；PEMS；重型柴油车；污染物排放