公交车用柴油机性能优化

Optimization of Bus Diesel Engine Performance

本文对典型城市公交车进行工况分析,公交车车速多在低速和中速行驶,高速较少,其中车速低于10 km/h的工况达55.8%,而发动机主要运行在怠速工况和低速中等负荷工况,该工况占比达58.9%。针对典型城市公交车的运行特点,明确发动机的优化方向,即降低怠速工况和低速中等负荷工况的油耗,同时优化该公交车的动力性,提升该公交车的舒适性。本文从发动机排量的选择、进排气系统的优化和电控系统参数优化标定等方面优化发动机。采用优化后的发动机,公交车起步加速性能提升了约8.2%;超越加速性能提升了10.9%;整车百公里油耗降低2.65 L/100 km,整体油耗降低了9.1%,效果明显。

In this paper, the working conditions of typical urban buses are analyzed. The speed of buses is mostly at low speed and medium speed, and the speed is less than high speed, 55.8% of which is less than 10km/h. The engine mainly runs at idle speed and low speed and medium load, accounting for 58.9%. According to the operation characteristics of typical urban buses, the optimization direction of the engine is clarified, that is, to reduce the fuel consumption at idle speed and low speed and medium load conditions, and to optimize the power performance of the bus and improve the comfort of the bus. In this paper, the engine is optimized from the selection of engine displacement, the optimization of intake and exhaust system and the optimization and calibration of electronic control system parameters. Using the optimized engine, the bus’ s acceleration performance is improved by 8.2%. The acceleration performance was improved by 10.9%;The fuel consumption of the whole vehicle is reduced by 2.65L/100km, and the overall fuel consumption is reduced by 9.1%.