Design And Analysis Of Ultra-high Injector In Commonrail Injection System

In order to meet the increasingly stringent emission and fuel consumption regulations, the high pressure common rail system must be further improved performance. The high pressure common rail system is the most sophisticated and complicated part of the diesel engine system. As the most difficult part in terms of design and technology, injectors have a greater impact on engine performance. So to improve the pressure of fuel that the injector can spray is one of the hot research, having a great impact on engine performance. The aim of this study is to provide technical support for the design of ultra-high pressure injector in common-rail injection system, by theoretical research and simulation analysis.Based on the component parts and working principle of high-pressure injector in common rail system, the calculation assumption was proposed on the basis of this physical model, and mathematical models of the injector were developed. Then the high-pressure fuel injector was developed in the AMESim software and testified by experiments, which was to find out the influence of the fuel’s pressure and structure of injector on the jet performance. It turned out that the pressure influenced the performance of injector by the move of control valve.Taking the result of simulation analysis and the feature of typical fuel injectors into account, this paper put forward one new ultra-high pressure injector in common-rail injection system. The ultra-high pressure injector belongs to PADI(pressure amplified diesel injector).It has two solenoid valves to control the change between pressure amplified mode and common rail injection mode. This injector proposed one valve which combined control valve with reversing valve which was the critical modules in the structure of injector. This structure contributed to reducing the number of parts, simplifying the structure and shorten the length of fuel. This paper focuses on the design of the newly invented ultra-high pressure injector. The design process, structure, composition and the working principle and process of ultra-high pressure injector are stated in detail.Finally, In order to verify the feasibility of the design philosophy, this paper built the critical part in the structure of injector as the module of finite element analysis based on 3D modules, and then get the result of FEA to check the project.