双阀电控单体泵燃油系统循环喷油量波动量化分析与控制方法研究

The electronic unit pump (EUP) fuel injection system is one of the nuclear sophisticated technologies for energy savings and pollutant reductions used in marine diesel engine. However, the application of EUP system is limited owning to its incompetence in controlling injection pressure and rate flexibly. While the double-valve electronic controlled fuel injection system combined the EUP and electronic controlled injector together, which can achieve advantages such as controlling injection pressure and rate neatly and independently, has a bright prospect for application in marine diesel engines. Whereas the cycle fuel injection quantity (CFIQ) of the double-valve fuel injection system is unstable due to highly complex and non-linear interaction between multi- physics parameters. It is noteworthy that the stable of CFIQ is the key problem for equipping marine diesel engine with double-valve fuel injection system. The project classified the factors that caused cycle fuel injection quantity variation (CFIQV) into three types through developing numerical simulation model and establishing test bench of the double-valve fuel injection system coupled by multi-physics fields. Factors including CFIQV thanks to the change of parameters in lifecycle, CFIQV in single pump-line-injector caused by manufacture precision and CFIQV led by the complicated effect involved electromagnetic, mechanical and hydraulic actions in the system are taken into considered. The generation mechanism of the CFIQV of the double-valve electronic unit pump fuel injection system is revealed by quantitative analyzing key parameters' influence on CFIQ using correlative analysis, Monte Carlo analysis and system decoupling methods, also control method for CFIQV is found. The results of this project have important theoretical significance for perfecting and developing of the double-valve electronic controlled fuel injection system. Moreover, the achievements of the study will help to promote development of collaborative simulation technology of the system coupled with multi-physics fields such as electromagnetic, mechanical and hydraulic fields.

电控单体泵燃油系统是船用柴油机节能减排的先进核心技术之一。然而，由于其喷油压力、喷油规律不能灵活控制，应用受到限制。将电控单体泵与电控喷油器相结合的双阀电控燃油系统具有喷油压力、喷油规律控制灵活且独立的优点，应用前景明朗。但由于其多参数相互作用的高度复杂非线性导致了循环喷油量波动，而循环喷油量稳定性是决定其成功匹配柴油机的关键。本课题建立多物理场耦合的数值模型和试验装置，将引起循环喷油量波动的因素解析为三种形式：1）寿命周期内系统参数变化引起的循环喷油量变化；2）批生产中因制造精度产生个体之间的循环喷油量差异；3）由于复杂机械、液力、电磁作用引起的循环喷油量波动。分别利用相关性分析方法、蒙特卡罗方法、系统解耦方法对决定循环喷油量波动的关键参数进行量化分析，揭示产生机理，提出控制方法。本课题的完成对双阀电控单体泵系统的发展和完善具有重要理论意义，并促进机械、液力、电磁系统协同仿真技术的发展。

双阀电控单体泵系统将电控单体泵与电控喷油器相结合，不但能够实现高的燃油喷射压力、灵活可控的喷油定时和精确的喷油量控制，还能够柔性的调节喷油速率和启喷压力，是具有重要应用前景的一种新型电控燃油系统。但由于其多参数相互作用的高度复杂非线性导致了循环喷油量波动，而循环喷油量稳定性是决定其成功匹配柴油机的关键。针对双阀电控单体泵燃油系统的喷油控制问题，本项目首先建立了双阀电控单体泵燃油喷射系统的单缸数值仿真模型和多缸耦合数值仿真模型；还建立了双阀电控单体泵系统试验装置；利用试验装置对双阀燃油系统的喷射特性和稳定性进行研究，并对双阀电控单体泵系统的数值仿真模型进行标定和验证；在全工况平面内，研究了双阀电控单体泵系统的协同喷射特性和循环喷油量波动特性，在不同控制模式下，计算了循环喷油量的波动范围，并揭示了不同特性参数对循环喷油量的影响机理；利用相关性和量化的研究方法对三类循环喷油量波动进行了量化和相关性研究，得出了整个系统中影响循环喷油量波动的关键参数，并通过分析系统状态矩阵的秩与特征值得出了系统动态喷射稳定性的变化规律；研究了燃油系统高压部分主要结构特性参数及控制特性参数对三次喷射的喷油量和后喷油速率的影响机理；结合低压供油系统，对系统低压供油特性的影响因素与系统压力升高率变化规律进行了分析；针对不同工况下溢流控制阀与针阀控制阀的电磁阀响应时间差异，对双阀电控单体泵系统电磁阀响应时间变化进行了研究，得出了结构参数与控制参数对系统电磁阀响应时间的影响规律。通过研究发表学术论文31篇，其中SCI收录8篇、EI收录13篇；申请发明专利21项、其中已授权8项。参加国内会议2次，国际会议4次，并作分组报告。本课题的完成对双阀电控单体泵系统的完善和发展具有重要理论意义，从而推进先进燃油系统的共性基础理论研究，并促进机械、液力、电磁系统协同仿真技术的发展。