【作者】 张平；

【导师】 杨延相；

【作者基本信息】 天津大学 ， 动力机械及工程， 2009， 博士

【摘要】 燃油喷射技术体系的核心是燃油喷射单元(喷嘴)。本文旨在基于FAI基本原理、实现一种同时适用于进气道喷射(PI)和缸内直喷(DISI)的燃油喷射技术,并对小型汽油机FAI技术产业化过程中的若干关键技术进行深入研究,以建立一种新型的燃油喷射技术体系。研究中首先以MFUD0007(FAI燃油单元的一种)为例,介绍FAI基本原理,并建立其性能测试和评价方法;首次通过试验方法研究FAI燃油单元的喷油规律。在解决FAI燃油单元和ECU生产一致性问题时,首次对FAI燃油单元制造散差的产生机理进行深入分析,在此基础上提出了FAI燃油单元的制造散差DOP概念,给出燃油单元的流量测试方法和非线性误差的分析方法;通过对制造散差(DOP)的统计分析结果表明,制造散差可能带来最大达10%的喷油量控制误差,并且对DOP的控制方法是有效的。首次对FAI燃油单元和ECU进行系统地可靠性设计。在对FAI燃油单元和ECU主要失效模式进行分析的基础上,提出提高燃油单元稳定性和持久性的关键技术——柱塞/电枢分体结构,受力分析结果表明该结构相对于整体式结构而言,柱塞所受的扭矩和压力腔所受的侧向力都能减小一倍左右。接着,制定燃油单元和ECU的可靠性试验方案,根据可靠性试验中需要,开发了燃油单元综合流量测试台、燃油单元磨合测试台、BOACH长管法喷油规律测量装置等设备。对“柱塞/电枢分体结构”可靠性试验结果表明,该结构持久性能够达到设计指标。在试验中也意外发现在压力腔设计上,其轴向尺寸越大,工作寿命就越长。针对FAI体系的开发和应用,开发了一套FAI系统开发环境。开发环境软件系统采用面向对象的编程方法,结合Windows操作系统的32位编程技术来实现。硬件系统主要包括HIL硬件、高速数据采集系统等。首次将FAI体系应用在二轮车用FAI进气口喷射技术上,并以SFP0002型汽油机管理系统为例,研究FAI进气口喷射技术在二轮车上的应用,提出FAI进气口喷射技术控制策略。在对CG125电喷摩托车进行道路强化耐久试验前后试验数据表明,能轻松达到排放法规要求,并满足10000 km以上的排放耐久性要求。更多还原

【Abstract】 The essential part of fuel injection system is the injector. The study is based on the theory of FAI(Finely Atomized Injection) and develops a fuel injection technology that can be fit for PI system and DISI system at the same time. Further studies are carried out on the industrialization of the FAI technology for small gasoline engine and a new fuel injection system is established.Firstly, the fundamental working principle of MFUD0007 (which is one type of the FAI injectors) is presented as an example. The performance test method of FAI injectors is developed and the FAI injection characteristic is studied by the method of experiments for the first time.The mechanisms of Dissipation of Production (DOP) are studied and the concept DOP of is presented during the study on the consistency of FAI injectors. Then, the fuel flux measured method and non-linear error control method are presented to ensure the consistency of the fuel injection unit. The statistical analysis results on DOP show that the deviation of the fuel flux brought out by DOP may be up to 10% and the control method to DOP is effective. A systemicly study on the reliability of the FAI fuel unit and ECU is carried out for the first time. After analyzing possible reasons for failure in the FAI fuel unit and ECU, the technology with the piston separated from armature is introduced, and the mechanical analysis of the piston shows that the force and torque of the piston acting on the pressure cavity are almost decreased by one half. An experiment is planned to test the reliability of the FAI fuel unit and ECU. Some facilities, such as fuel test complex, fuel unit grinding equipment and injection rule test apparatus, are developed. The test on the technology with the piston separated from armature show that it can be up to more stable. One conclusion is discovered; the lengthening of the axis of the pressure cavity can prolong the life of the FAI fuel unit.The FAI Development system was developed for the developing and application of the FAI technology. During software programming, the object-oriented method and 32-bit technique of WINODWS are used. The hardware consists of HIL hardware (hardware in the loop) and the High-Speed-Acquisition Card.The SFP0002 system of FAI is given as an example. SFP0002 is designed for two wheelers under 150cc and a control strategy is designed for it. The CG125 engine equipped with SFP0002 is tested on a strength condition. The test results show that it can easily pass emission limits, and it can also match the requirements of a 10000km road test.更多还原