基于13 L国六重型柴油机，通过台架试验探究了机油泵、水泵以及空压机三种附件的优化对柴油机经济特性和排放特性的影响，并得出各附件的贡献度占比，为后续优化提供方向。结果表明：在原机的基础上，通过更换小流量机油泵、小流量水泵以及采用空压机节能模式或者拆除空压机，无论是在外特性工况点还是在最佳热效率工况点，燃油消耗率均有不同程度的降低，热效率得以提升。对于附件优化前后的排放，在外特性工况点和最佳热效率工况点，机油泵的优化使排温升高、NO_x增加、Soot降低，而水泵和空压机的优化使排温降低、NO_x降低、Soot升高。最佳热效率工况点下，三个优化附件中，水泵的优化对热效率提升贡献度最大，占比高达43.56%，而机油泵和空压机的优化贡献度相近，约为28%。

Based on a 13 L China Ⅵ heavyduty diesel engine, the influence of optimizing the accessories such as oil pump, water pump and air compressor on the fuel economy and emission characteristics of diesel engine was explored and analyzed through bench tests, and the contribution ratio of each accessory was acquired, which provided the direction for the subsequent optimization. The results show that replacing the lowflow oil pump, low-flow water pump and adopting the energysaving mode of air compressor or removing the air compressor on the original engine can reduce the specific fuel consumption to different degrees and improve the thermal efficiency both at the external characteristic working point and the optimal thermal efficiency working point. Under the two mentioned conditions, the optimization of oil pump resulted in an increase in exhaust temperature and NOx emission and a decrease in soot emission, while the optimization of water pump and air compressor led to a decrease in exhaust temperature and NOx emission and an increase in soot emission. At the optimal thermal efficiency working point, among the three optimization accessories, the optimization of water pump had the largest contribution to the improvement of thermal efficiency as much as 43.56%, while the optimization contributions of oil pump and air compressor were both about 28%.