基于FLUENT的后混合磨料水射流喷嘴内流场的数值模拟

Numerical Simulation of Post-mixed Abrasive Water Jet Nozzle Based on FLUENT

以后混合磨料水射流喷嘴为研究对象,基于多相流动的欧拉模型,应用FLUENT流体分析软件对几种典型后混合磨料喷嘴的内流场进行数值模拟和仿真,得到压力分布、速度分布、湍流能量分布。结果表明:喷嘴内由于涡旋的形成损耗了部分能量,使得射流出口速度和动能明显降低;存在一个最优圆柱长度使得磨料出口速度达到最大值,其长度为喷嘴出口直径的23～37倍时,磨料得到最高的出口速度;喷嘴内流体紊动能的分布主要集中在喷嘴近壁区和几何形状变化较大的区域。

According to the Eulerian multiphase model of multiphase flow,simulation of the interior flow of several dynamic performance inside post-mixed abrasive water jet nozzle was carried out by FLUENT.A series of simulation results such as pressure distribution,velocity distribution,turbulent kinetic energy distribution were obtained.The results indicate that the exit velocity and kinetic energy is significantly reduced because of the vortex formation making part of the energy loss.And there is optimized nozzle length to get maximum velocity of abrasive particles inside nozzle.The maximum exit velocity of abrasive particles is obtained when the cylinder part is 23～37 times of the inside diameter.The turbulence distribution inside the nozzle can be focused on the near wall region and the area which geometry has larger changes.