Abstract A real driving emissions test procedure was introduced as a supplement to the chassis dynamometer test to diminish the discrepancy between on-road emissions and type approval certification emissions. In this study, on-road NOx emissions from a 2.2 L diesel vehicle equipped with a lean NOx trap were measured not by a portable emissions measurement system but by NOx sensors and an exhaust flow meter. This method provides a strategy for analyzing on-road NOx emissions with a measurement system that is relatively cheap, light and simple. The effects of ambient temperature, diesel particulate filter regeneration, traffic congestion, NOx conversion efficiency and uphill/downhill sections on NOx emissions were evaluated by comparing the NOx emissions characteristics using engine-out and lean NOx trap-out NOx sensors. NOx emissions in congested traffic conditions were 29% higher than those in smooth traffic conditions. NOx emissions at 33 °C were 55% higher than those at 27 °C. Additionally, NOx emissions under specific conditions with diesel particulate filter regeneration were 30% higher than those under normal conditions. The average on-road NOx emission factor for all test cases was 7.35, but this value decreased to 5.7 when an ambient temperature corrective factor (1.6) was applied for extended test conditions.

中文翻译：

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环境温度、DPF 再生和交通拥堵对符合欧 6 标准的配备 LNT 的柴油车在实际驾驶条件下的 NOx 排放的影响

摘要 引入实际驾驶排放测试程序作为底盘测功机测试的补充，以减少道路排放与型式认证排放之间的差异。在这项研究中，配备稀有 NOx 捕集器的 2.2 升柴油车辆的道路 NOx 排放不是通过便携式排放测量系统测量的，而是通过 NOx 传感器和排气流量计测量的。该方法提供了一种使用相对便宜、轻便且简单的测量系统分析道路 NOx 排放的策略。环境温度、柴油微粒过滤器再生、交通拥堵、NOx 转化效率和上坡/下坡路段对 NOx 排放的影响通过比较使用发动机输出和稀薄 NOx 捕集式 NOx 传感器的 NOx 排放特性进行评估。拥堵交通条件下的氮氧化物排放量比顺畅交通条件下的排放量高 29%。33 °C 时的 NOx 排放量比 27 °C 时高 55%。此外，在柴油微粒过滤器再生的特定条件下，氮氧化物排放量比正常条件下高 30%。所有测试案例的平均道路 NOx 排放因子为 7.35，但当环境温度校正因子 (1.6) 应用于扩展测试条件时，该值降至 5.7。