Normality and integrity of CO₂ window.

This study aimed to investigate the impact of altitude, cold start, ambient temperatures, and driving behaviors on the Real Driving Emissions (RDE) of China VI standard light-duty gasoline vehicles. Tests were conducted on actual roads and in vehicle emission environment simulation laboratories at altitudes of 700 m, 1,300 m, 1,900 m, and 2,400 m in Yunnan. The results showed that: (1) as altitude increased, the CO emission factor exhibited a positive correlation trend, peaking at 2400 m with a 2.56-fold increase compared to 700 m. The NOX emission factor displayed an “N” distribution, with aggressive driving at 1900 m yielding 1.89 times higher emissions than normal driving and 3.02 times higher than low-temperature driving; (2) under low-temperature rotating wheel conditions, PN emission factors were 7.55 times higher than normal driving and 71.71 times higher than aggressive driving, indicating that driving behavior significantly influenced NOX emissions, while low-temperature environments had a greater impact on PN emissions; (3) compared to non-cold-start conditions, the cold-start phase increased urban CO, NOX, and PN emission factors by 4.72% to 225.00%, 0.19% to 15.38%, and 6.45% to 430.36%, respectively, with total emission factors increasing by 0.07% to 0.55%, 0.00% to 6.00%, and 1.03% to 242.64%.本研究旨在探究海拔、冷启动、环境温度与驾驶行为对国六（China VI）标准轻型汽油车的实际行驶排放（Real Driving Emissions，简称RDE）的影响。试验于云南地区海拔700 m、1300 m、1900 m、2400 m的实际道路，以及车辆排放环境模拟实验室中开展。研究结果表明： (1) 随着海拔升高，CO排放因子呈正相关变化趋势，在2400 m时达到峰值，较700 m时提升2.56倍。NOₓ排放因子呈现“N”型分布；在海拔1900 m工况下，激进驾驶的NOₓ排放较正常驾驶高1.89倍，较低温驾驶高3.02倍； (2) 低温转轮工况下，PN排放因子较正常驾驶高7.55倍，较激进驾驶高71.71倍，这表明驾驶行为对NOₓ排放影响显著，而低温环境对PN排放的影响更为突出； (3) 相较于非冷启动工况，冷启动阶段城市工况下的CO、NOₓ及PN排放因子分别提升4.72%~225.00%、0.19%~15.38%及6.45%~430.36%，总排放因子分别提升0.07%~0.55%、0.00%~6.00%及1.03%~242.64%。