摘要
针对液压自由活塞柴油机的特点提出了共轨液压式柴油喷油系统,即利用液压自由活塞柴油机的高压油路替代供油系统的高压油泵。通过对共轨液压式喷油系统的原理分析,利用活塞式供油规律测试仪对其喷油规律展开离线研究,研究了不同驱动压力、不同喷射频率条件下的循环喷油量、喷油延迟时间的变化规律。为进一步研究发动机实际运行过程中气门控制油路等对喷油过程产生的影响,在线对循环喷油量进行了测量。结果表明:由于喷油器驱动油路和气门驱动油路连接在一起,气门驱动供油造成了喷油器驱动油路的压力波动,从而使得循环喷油量变动范围变大(-6.9%9.5%),最终影响发动机稳定运行。对发动机气门及喷油驱动油路改进后进行连续运行试验,试验研究结果表明:循环喷油量的波动及实际喷油位置的变化都会影响液压自由活塞发动机连续稳定运行,要实现液压自由活塞发动机连续可靠稳定运行,必须减小循环喷油量波动和喷油延迟时间。
A hydraulic electronic unit injector was proposed for a hydraulic free piston diesel engine. The high pressure pump for the injector was replaced by the high pressure rail used for the engine. With the analysis of hydraulic electronic unit injector principle, the fuel injection characteristics were researched with Inov8 AKRIBIS II. The research focused on the effects of drive pressure and injection frequency on cyclic fuel injection quantity and injection delay. In order to analyze the effect of the rail pressure for the engine valve actuation on fuel injection process, an online test was carried out to measure fuel injection quantity. Results show that the valve actuation enlarges the cyclic fuel injection fluctuation (from --6.9 % to + 9.5% ) because of the connection between the valve actuation and injector through their pressure rail, which affects stable engine operation. After the improvement of the high pressure rail system, a continuous engine test indicates that the fluctuation of cyclic fuel injection quantity and actual injection position affect the stability of engine operation, therefore the fluctuation of cyclic fuel injection quantity and injection delay should be reduced for the purpose of stable continuous engine operation.
作者
张栓录
赵长禄
赵振峰
张付军
赵锐娜
ZHANG Shuanlu ZHAO Changlu ZHAO Zhenfeng ZHANG Fujun ZHAO Ruina(School of Mechanical Engineering,Beijing Institute of Technology, Beijing 100081, China Beijing North Vehicle Group Corporation,Beijing 100072,China)
出处
《内燃机工程》
EI
CAS
CSCD
北大核心
2017年第4期1-6,共6页
Chinese Internal Combustion Engine Engineering
基金
高等学校博士学科点专项科研基金资助项目(20131101120019)~~
关键词
自由活塞发动机
喷油
液压柱塞
循环变动
泵喷嘴
free piston engine
fuel injection
hydraulic plunger
cyclical variation
unit injector