超高压共轨燃油系统多次喷射循环喷油量波动特性研究

Ultra-high pressure common rail fuel system is the cutting-edge technology of modern diesel engine for energy conservation and emission reduction. Multiple injections is the key for the development of the system, which is of great significance for improving diesel engine economy and controlling emissions. However, because of the system involves coupling of multi-energy fields including electric field energy, magnetic field energy, mechanical energy and hydraulic energy, the influence rule and generation mechanism of interaction effects between multi-energy fields parameters on cyclic fuel injection quantity of multiple injections are not clear as yet. Therefore, the issues are taken into consideration in this project. The power bond graph numerical model of multi-energy fields coupling for the system is developed based on the energy field and power flow. The relationships of transformation and mutual logic for the energy fields are obtained, and the influence mechanism and corresponding relationship between pressure fluctuation and cyclic fuel injection quantity are revealed. On this basis, the significant influence parameters on cyclic fuel injection quantity fluctuation during the multiple injections are obtained by the significance analysis methodology. After that, the response surface is established by means of correlation analysis, thus, the coupling mechanism of multi-energy fields parameters will be revealed. Then, the quantization index database of the significant interaction parameters on cyclic fuel injection quantity of multiple injections will be built. Besides, the algebra decoupling of the coupling relationship between multi-energy fields parameters will be realized by the investigation on decoupling method. Finally, the correction control strategy for the cyclic fuel injection quantity fluctuation of multiple injections will be proposed. The achievements of this project will provide theoretical foundation for the design of ultra-high pressure common rail fuel system and the stability controlling of fuel injection, and have great academic value for the development of diesel engine electronic control fuel system.

超高压共轨燃油系统是现代柴油机节能减排的前沿技术，多次喷射作为其发展的关键对提高柴油机经济性和控制排放意义重大。而由于系统涉及电场能、磁场能、机械能、液压能多能量场耦合，导致多能域参数间交互作用对多次喷射循环喷油量的影响规律和产生机理尚不清楚。本课题拟以此为研究对象，基于能量场和功率流建立系统多能域耦合的功率键合图数值模型，得出能量场间转换与相互逻辑关系，揭示压力波动对循环喷油量的影响机理与对应关系。在此基础上，利用显著性分析方法得到多次喷射循环喷油量波动显著影响参数，通过相关性分析方法建立响应面，揭示多能域参数耦合作用机理，建立影响多次喷射循环喷油量的显著交互作用参数量化指标数据库；通过解耦方法研究实现多能域参数间耦合关系的代数解耦，针对多次喷射循环喷油量波动提出修正控制方法。本课题的完成将为超高压共轨燃油系统设计及油量稳定性控制提供理论支撑，对柴油机电控燃油系统开发具有重要的学术价值。

超高压共轨燃油系统是现代发动机节能减排的前沿技术，揭示其多次喷射循环喷油量波动产生机理和波动规律，保证多次喷射循环喷油量一致性，是当前超高压共轨燃油系统亟待解决的技术难题。本项目推导得到了超高压共轨燃油系统状态方程，建立了多能域耦合的功率键合图数值模型。开展了压缩波与膨胀波耦合关系的理论研究，得出了压力波动对循环喷油量的影响机理与对应关系。对不同喷射模式下循环喷油量波动特性展开了分析，得到了对循环喷油量波动影响显著的关键参数，建立了影响循环喷油量波动的显著交互作用特性参数量化指标数据库。开展了多能域参数解耦方法研究，揭示了多次喷射过程本质规律及独立于输入和输出的内在特性。建立了多次喷射循环喷油量波动频率等效模型，研究了系统多能域参数对多次喷射循环喷油量波动频率的影响规律，提出了以多能域参数、轨压、多次喷射间隔及喷油脉宽等为特性参数的多次喷射循环喷油量修正方法，实现了超高压共轨燃油系统多次喷射循环喷油量的一致性和稳定性控制。. 通过本项目研究支持负责人获批主持中国博士后科学基金第13批特别资助（资助编号2020T130140）；获中国专利银奖、World Congress on Internal Combustion Engines BEST PAPER、中国发明协会发明创新一等奖、船舶与海洋工程行业专利金奖4项科研奖励；受邀担任《内燃机学报》编委会特邀编委；共发表学术论文18篇（其中第一或通讯作者15篇，第一标注15篇），其中SCI收录8篇（其中TOP论文3篇）、EI收录7篇（其中国内一级学会主办的学术期刊论文4篇）、北大中文核心期刊收录2篇；专利转化1项，授权PCT国际专利1项，申请中国发明专利2项；登记软件著作权4项；参加国内学术会议2次，国际学术会议4次；培养博士后1人、博士研究生2人、硕士研究生4人。本项目的完成将为超高压共轨燃油系统的设计及循环喷油量波动控制提供技术支撑，对推进自主知识产权的发动机电控喷油系统开发具有重要理论和实际意义。