【摘要】 为探讨重型汽车型式认证排放检测工况欧洲瞬态循环ETC工况与城市公交车实际行驶工况的符合性,对两辆典型的大型LPG公交车,沿广州市中心区两条典型公交线路运行,进行了公交车城市行驶逐秒的车速与变速挡位的测试,基于测试数据计算出对应的发动机转速与转矩,并将其与ETC城市工况比较。结果表明,相比ETC城市工况,LPG公交车实际运行工况中发动机怠速时间占比大1.4倍,零转矩占比大0.8倍,平均转速低38.34%,平均转矩低59.09%。在转速分布方面,实际行驶工况主要集中在低转速区,而ETC城市工况则主要分布在中、高转速区;至于转矩分布,实际行驶工况主要集中在低转矩区,而ETC循环则比较宽广地分布在整个转矩范围。总之,LPG公交车实际运行工况与ETC城市工况存在较明显的差异。更多还原

【Abstract】 To investigate the conformity of the ’urban streets’ part of ETC cycle to the real-world driving cycle of heavy duty city buses,a test of bus city driving is conducted on 2 typical LPG city buses running on 2 typical routes in Guangzhou City with vehicle speed and gear position measured for each second.Based on these data the corresponding speed and torque of engine are then calculated and compared with that in the urban part of ETC cycle.The results show that compared with the ETC cycle,the time proportion of idling in real-world driving is 1.4 times higher,and 0.8 times higher for zero-torque mode,38.34% lower in average speed,and 59.09% lower in average torque.In speed distribution the real-time driving mode is mainly concentrated at low speed range while the ETC cycle is basically at medium and high speed regions.As for torque distribution the real-time driving mode is mainly concentrated at low torque region while the ETC cycle is rather widely spread over the whole torque range,so there is a significant difference between the real-world driving mode of LPG city buses and the urban part of ETC cycle.更多还原