柴油机喷油器结构参数与磨料流加工效果关联的研究

Study on the Relationship Between the Structural Parameters ofDiesel Injectors and the Effect of Abrasive Flow Machining

基于磨蚀模型和多相流离散相模型建立了柴油机喷油器磨料流加工过程的CFD计算模型。在验证基础模型的有效性后,分别针对喷孔直径、喷孔锥角和交点位置三种结构参数进行变参数模拟计算。通过对加工域颗粒流速、湍流强度和磨蚀率的分析,获得了喷油器主要结构参数对液力研磨加工的影响机理:喷孔直径和喷雾锥度的变化对喷孔壁面磨蚀量的影响较大,随着两者的增大,喷孔壁面的磨蚀量有所增加;交点位置由上至下的变化对喷孔壁面磨蚀量的影响较小,但是喷孔入口处磨蚀量有所增加。

Based on the erosion model and the discrete phase model of multiphase flow,the CFD calculation model of the hydraulic grinding process of diesel injector was established.After verifying the effectiveness of the foundation model,the variable parameter simulation calculation was carried out for three structural parameters of the spray hole diameter,the spray cone angle and the intersection point position,respectively.Through the analysis of particle velocity,turbulence intensity and abrasion rate in machining area,the influence mechanism of main structure parameters of injector on hydraulic abrasive machining was obtained.The change of nozzle diameter and spray taper has a great influence on the abrasion amount of the jet hole wall.With the increase of both,the abrasion amount of the jet hole wall surface increases.The change of intersection position has little effect on the abrasion amount of nozzle wall,but the abrasion at the nozzle inlet increases.