| Abrasive water jet cutting technology is a new type of processing technology that has gradually emerged in recent years.It is currently widely used in fields such as machinery,mining,metallurgy,military industry,and food.This article uses numerical simulation methods to study the mechanism and model of abrasive water jet cutting.When using the Lagrange method to simulate abrasive water jet machining,due to the large deformation problem involved,the grid will be severely distorted,resulting in computational difficulties.When using the ALE method,it is difficult to simulate the mixing mechanism between abrasive particles and water jet.Therefore,this paper proposes to use the SPH coupled FEM method to study the accelerated motion process of abrasive particles in the post mixed abrasive water jet,the removal mechanism of target materials at micro layers,and the influence of different cutting parameters on the cutting effect of steel plates.The specific research content is as follows:Firstly,a brief introduction was given to the development history and research status of abrasive water jet technology.The operating conditions of the turbocharger that produces high-pressure water in the abrasive water jet cutting system were studied,and the force analysis of its moving components was conducted.The differential equation of the motion of the moving components was established.A simulation model of high-pressure water generated by an abrasive water jet system was established using AMESim.The pressure and flow characteristics at the nozzle inlet were analyzed under different accumulator volumes,servo valve reversing time,and when single,double nozzles and single,double group turbochargers were working separately.Secondly,based on the mixing mechanism of post mixed abrasive water jet abrasive and water flow,a model including nozzle,water flow,and abrasive particles was established using the SPH-FEM coupling method to simulate the mixing and acceleration of a single abrasive particle with water flow inside the nozzle.Through simulation,the effects of jet pressure,abrasive particle density,and abrasive particle diameter on the motion law of abrasive particles in the nozzle were analyzed.Applying the wear theory of Hutchings et al.on plowing deformation and cutting deformation to the study of abrasive water jet,a simulation model of abrasive particle target impact was established to study the removal mechanism of target material by abrasive particles at the micro level.The target was modeled using the SPH-FEM method,and the material removal law of the target under different shapes of abrasive particles and continuous impact of multiple abrasive particles was analyzed through numerical simulation.Finally,the influence of abrasive water jet on cutting steel plate under different cutting parameters is studied,and a simulation model of abrasive water jet cutting steel plate is established.The influence of three main factors,namely abrasive concentration,jet pressure,and cutting angle,on the cutting effect of abrasive water jet cutting steel plate is studied.This article establishes a numerical simulation model to study the acceleration motion law of abrasive particles inside the nozzle in the post mixed abrasive water jet,as well as the removal mechanism of target materials at the micro layer level.It also studies the influence of different cutting parameters on the cutting effect of steel plates.The research conclusion provides a reference for subsequent prediction model establishment and process parameter optimization. |
