后混合磨料射流固液两相流动特性OA北大核心CSTPCD

For the problem of uneven solid-liquid two-phase mixing and low energy density in the post-mixed abrasive jet,the CFD-DEM coupled numerical simulation method was adopted,the fluid-phase velocity distribution was analyzed,and discrete-phase trajectory and solid-liquid two-phase mixing characteristics were analyzed.After experimental comparison and verification,the results show that the abrasive particle concentration in the mixing chamber is higher at both ends and lower in the middle.When the jet velocity is insufficient to overcome vortex effects,particle blockage occurs,impairing their movement.Under ideal conditions,abrasive particles collide with the water jet core without large-angle collisions with the wall.At inlet velocities of 150 m/s and 600 m/s,56%of the abrasive particles have the shortest residence time in the nozzle.However,at 600 m/s,particle aggregation and dispersion are more pronounced,resulting in lower energy efficiency.Inside the focusing tube,particles exhibit circumferential motion,with a tangential velocity of 2.12 m/s at 150 m/s.Increasing the focusing tube length can reduce tangential velocity and improve machining efficiency,among them,the 60 mm length is the optimal length.These findings can provide guidance for optimizing abrasive water jet nozzle design and application.