基于CFD-DEM仿真的喷丸工艺参数优选

Optimization of Shot Peening Process Parameters Based on CFD-DEM Simulation

目的综合考虑喷丸过程的能量效率,以最少喷打时间和最小比能为目标进行喷丸工艺参数优选。方法通过分析弹丸群以单对称单元模型喷打的弹痕排布方式,以及满足一定覆盖率时平均每个弹丸形成的弹坑面积,得到随机喷打时的材料去除体积,进而得到能量利用效率。以喷丸入口压强、弹丸直径和弹丸流量三个工艺参数为变量,以一定覆盖率下的最小喷丸时间和最大能量利用率为目标,建立喷丸工艺参数优化模型。通过建立CFD-DEM气固两相耦合的喷丸仿真模型,进行仿真实验,得到出口弹丸速度与工艺参数的关系,进而得到每组实验的喷丸时间和能量利用率。结果通过16组仿真实验,得到第4组工艺参数为最优喷丸工艺参数组合,即入口压强为0.5 MPa,弹丸直径为1.0 mm,弹丸流量为0.6 kg/s。结论CFD-DEM仿真模型能够得到出口弹丸速度与其他工艺参数的关系,喷丸工艺参数优化模型能够兼顾效率和能量利用率,并筛选出最优工艺参数组合,为喷丸工艺参数决策提供指导。

This work aims to select optimal shot peening process parameters so as to realize the minimum shot peening time and maximum energy efficiency by considering energy efficiency of shot peening process as a whole. Material removal volume during random shooting was obtained by analyzing arrangement of projectile group in one symmetry cell model and average crater area formed by each projectile when certain coverage was reached, and energy utilization efficiency was further obtained. With shot peening inlet pressure, projectile diameter and projectile flow rate as variables, were taken as process variables, an op- timization model was established for shot peening process parameters to minimize shot peening time and maximize energy effi- ciency at certain coverage rate. A coupling gas-solid CFD-DEM simulation model was established for shot peening to obtain re- lationship between outlet projectile velocity and process parameters. Sixteen groups of simulation experiments showed that process parameters of the 4th group were the optimal combination of shot peening parameters： inlet pressure intensity of 0.5 MPa, projectile diameter of 1.0 mm, and projectile flow rate of 0.6 kg/s. This simulation model can establish the relationship between outlet projectile velocity and other process parameters, and the optimization model can allow for both efficiency and energy utilization rate, select optimal combination of shot peening process parameters and provide guidance for decision making regarding shot peening parameters.