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.