GDI喷油器针阀动力学特性研究

针阀动力学行为是影响GDI(汽油直接喷射式）喷油器工作稳定性和可靠性的关键因素。为了揭示不同参数对针阀动力学特性的影响机理，以某款GDI多孔喷油器为对象，依据针阀的受力特点建立了针阀动力学模型和GDI喷油器AMESim工作过程仿真模型，仿真分析了阀座锥角、阀座与钢球的接触方式、阀针运动质量等参数对针阀动力学特性的影响规律。结果表明：适当减小阀座锥角、增大阀座与钢球的接触面积、减小针阀运动质量可有效抑制开启或落座过程中针阀的振荡幅度。根据仿真分析结果对GDI喷油器的结构进行了综合改进，结果表明，结构改进后，GDI喷油器针阀的动力学特性得到显著改善。

Research on Kinetics Characteristics of Needle in GDI Injector

Kinetics behaviors of the needle had an important impact on stability and reliability of the GDI injector. With a GDI injector as the object, this paper established a kinetics model of the needle and an AMESim simulation model of the GDI injector based on mechanical characteristics in order to reveal the influence mechanism of different parameters. The paper analyzed influence rules of different parameters through simulation, the results show that reducing seat cone angle appropriate, increasing contact area between ball and needle, and reducing moving mass of the needle can suppress the amplitude of oscillation effectively. The paper proposed a comprehensively improved structure based on above analyses of the GDI injector. The final results show that kinetics characteristics of the needle can be improved significantly with the optimized new structure.