为研究气动喷砂枪喷射颗粒对喷嘴造成的冲蚀磨损情况,选取文丘里型气动喷砂喷嘴为研究对象,运用CFD软件对其内部流场及颗粒运动特性进行仿真模拟分析;通过改变收缩角度、颗粒粒径及质量流率进一步分析喷嘴冲蚀速率变化的规律。结果表明:喷嘴的冲蚀区域主要集中在喉管及收缩管出口区域;随着收缩角度的增加,喷嘴最大冲蚀速率逐渐增大,采用30°、45°收缩角度的喷嘴时,颗粒并未出现“回弹”的现象,采用60°收缩角度的喷嘴时,部分颗粒出现“回弹”现象,通过观察不同收缩角度喷嘴内颗粒撞击壁面的位置可知,撞击点出现“滞后”现象;喷嘴的最大冲蚀速率随颗粒粒径的增加先减小再增加再减小最终趋于稳定;喷嘴最大冲蚀速率随颗粒质量流率的增加逐渐增大,并且拟合曲线近似呈现线性关系。可见,应根据流体介质中实际颗粒粒径分布情况,合理控制颗粒的质量流率并选取喷嘴适宜的收缩角度以减轻颗粒对壁面的冲蚀作用。

 In order to study the erosion wear caused by the sprayed particles on the nozzle, Venturi type nozzle is selected as the research object,and its internal flow field and particle motion characteristics are simulated and analyzed by CFD software.Analysis on the variation law of nozzle erosion rate is carried out by changing the shrinkage angle, particle size and particle mass flow rate.The results show that the erosion area of the nozzle is mainly concentrated in the throat and shrinkage pipe outlet area.The maximum erosion rate of the nozzle increases gradually with the increase of the contraction angle.For nozzles with a shrink angle of 30° and 45°, the particles inside the flow field do not “rebound”.Fornozzle with a shrink angle of 60° , there is a “rebound” phenomenon in some particles.By observing the position of the particles hitting the wall surface in the nozzle with different shrinkage angles, it can be seen that there is a "lag" phenomenon at the impact point.The maximum erosion rate of the nozzle decreases with the increase of particle size, then increases, then decreases, and finally tends to be stable.The maximum erosion rate of the nozzle increases with the increase of the mass flow rate of the particles, and the fitting curve approximates a linear relationship.It can be seen that the mass flow rate of the particles should be reasonably controlled according to the actual particle size distribution in the fluid medium and the appropriate shrinkage angle of the nozzle should be selected to reduce the erosion effect of the particles on the wall surface.