重型柴油车实际道路排放与行驶工况的相关性研究

On-board emission from heavy-duty diesel vehicle and its relationship with driving behavior

采用SEMTECH-D车载排放测试仪测量了东风柴油卡车在城市实际道路工况以及等速和加速工况下的油耗及污染物排放状况．测试结果显示，测试卡车实际道路综合百公里油耗为17．8L，NOx、CO和Hc排放因子分别为3．96、8．86和2．15g ·km^-1．其中主干道路况相对较差，油耗与排放因子较高，是所有测试道路平均水平的1．3-1．8倍左右．研究结果表明，重型车油耗及污染物排放与各行驶工况下的速度、加速度均密切相关，车辆在高速加速行驶状态下易产生高排放．车辆在30～50km·h^-1速度区间内等速行驶时。油耗与排放因子最为经济且环境友好．车辆在加速行驶时，油耗与NOx、CO排放因子可达到城市实际道路平均水平的2．0、2．2、1．4倍，急加速时达到2．8、2．1、14倍．应用比功率概念可准确描述车辆在各运行工况下的排放水平，但在重型车上缺乏实验依据，有待进一步研究．

On-board emission measurement of Dongfeng heavy-duty diesel truck was conducted respectively on city reads at cruise ＆ acceleration conditions by using a portable emission measurement system （PEMS）, named SEMTECH-D. The results show fuel consumption and NOx, CO, HC emission factors on real world cycles are 17.8 L · 100km^-1 and 3.96, 8.86, 2.15 g·km^-1. The factors on arterial are higher than the other road types, which are nearly 1.3 - 1.8 times of the comprehensive ones. By analysis, the study illustrated that heavy-duty vehicle emission is strongly related with its speed and acceleration driving cycles. Higher pollutant emission rates were tested during the high speed and acceleration zone in the driving cycle map. The factors of fuel use and emissions during the steady speed of 30 - 50km·h^-1 were much lower than the other driving patterns, while the fuel use and NO,, CO emission factors during acceleration reached 2, 0, 2.2, and 1.4 times of the comprehensive ones and drastic acceleration will induce 2.8, 2.1 and 14 times, Furthermore, VSP can be utilized to precisely evaluate the vehicle emission level on various driving cycles, but further studies are needed since there is still no relative experiment data on VSP formation of heavy duty vehicles.