中文摘要：

分析了喷射距离对射流抛光效果的影响，基于计算流体动力学进行了喷射距离的分析和优化．通过构建射流抛光不同喷射距离的物理模型，采用能更好地处理流线弯曲程度较大的流动的RNGk-ε紊流模型应用于射流抛光的数学建模，使用SIMPLEC算法对射流模型进行数值计算，得到了不同模型的射流抛光冲击射流流场及工件壁面上的冲击压力、紊动强度、壁流速度分布．根据射流抛光对冲击射流特性的要求，比较和分析不同喷距模型的数值仿真结果，结果显示，射流抛光最优化喷距范围为喷嘴口径的10倍至12倍之间．

英文摘要：

The jet distance influences on the effect and precision of fluid jet polishing are analyzed. Based on the theory of Computational Fluid Dynamics, seven physics models with different jet distance are established. According to the characteristic of fluid jet polishing compared with kinds of fluid models, it is found that the RNG k-ε model is more suited to the fluid jet model because the RNG k-ε model can calculate the crooked badly streamlines＇ model. Then, these impinging models of fluid jet polishing with the SIMPLEC algorithm are simulated, the continuity fluid field, impinging pressure, turbulent intensity and wall velocity distributing of different jet distance models are gained. The demand of impinging jet characteristic to fluid jet polishing is analyzed. By researching the distributing of continuity fluid field, impinging pressure, turbulent intensity and wall velocity, it is found that the optimization value of jet distance is ten to twelve times of the diameter of nozzle.