电控单体泵全工况喷油量波动影响参数量化分析

Quantitative analysis on the electronic unit pump fuel injection quantity in overall operating conditions

电控单体泵循环喷油量的波动直接影响其匹配船用发动机的工作稳定性和一致性.为研究系统各关键特性参数对循环喷油量波动的影响规律及成因机理,利用AMESim数值模型,揭示了低压供油压力、凸轮型线速率、柱塞配合间隙、控制阀杆升程、衔铁残余气隙、控制阀杆配合间隙、喷油器开启压力、喷油器针阀升程和喷油器流量系数等关键参数对循环喷油量的影响规律.通过量化分析,得出各特性参数对循环喷油量波动影响的百分比量化指标,在全工况平面内,低压供油压力为0～20.2%,凸轮型线速率为20.6%～42.0%,控制阀杆升程为4.0%～16.5%,喷油器开启压力为3.7%～49.8%,喷油器针阀升程为0～16.5%,喷油器流量系数为2.6%～40.5%;同时,揭示了全工况平面内负荷特性和速度特性下各特性参数对应的循环喷油量波动的百分比量化指标规律.对影响循环喷油量稳定性的关键特性参数进行量化分析,可为实现电控单体泵燃油喷射系统全工况平面循环喷油量的稳定性设计、提高电控单体泵和船用柴油机性能的一致性提供理论指导.

Cycle fuel injection quantity（CFIQ） fluctuation of an electronic unit pump（EUP） influences stability and coherence of the marine diesel engine with which it is matched.The fluctuation of cycle fuel injection quantity influenced by characteristic parameters such as the fuel supply pressure,cam profile velocity,plunger matching clearance,control valve lift,anchor residual clearance,control valve matching clearance,injector opening pressure,injector needle lift,and injector flow coefficient were simulated by the Advanced Modeling Environment for Simulation of engineering systems（AMESim） simulation model for investigating the influence law and the generation mechanism of CFIQ fluctuation caused by variations of characteristic parameters.By quantitatively analyzing the simulation results,the percentage quantitative indexes of cycle fuel injection quantity fluctuation were obtained： percentage quantitative index of fuel supply pressure ranges from 0 to 20.2%,cam profile velocity from 20.6% to 42.0%,control valve lift from 4.0%~16.5%%,injector opening pressure from 3.7%~49.8%,injector needle lift from 0 to 16.5%,and injector flow coefficient from 2.6% to 40.5%.Finally,the variation law of percentage quantitative indexes on the load characteristic curve and speed characteristic curve in the overall operating conditions was summarized.The quantitative analysis results on the stability of the CFIQ can provide a theoretical guide for stability design and coherence performance improvement of the EUP fuel injection system and marine diesel engine in the overall operating conditions.