Simulation Study Of Abrasive Particle Dynamics In Magnetic Abrasive Finishing Of Inner Surface Of Pipe

With the development of China’s industry,all industries have higher requirements for the performance of mechanical equipment.As a common component for fluid transmission,pipe fittings with rough inner surfaces and microcracks seriously affect the stability of fluid transmission and the service life of pipe fittings.Therefore,it is necessary to perform surface finishing on the inner surface of pipe fittings.Magnetic abrasive machining technology,as a surface finishing technology,can overcome the disadvantage of traditional processing methods that are difficult to machine deep inside the pipe by controlling the movement of magnetic abrasive particles through a magnetic field.Additionally,its machining accuracy can reach the nanometer level.Therefore,it has been widely used in the field of inner surface finishing of pipe fittings.Magnetic abrasive is the most important processing medium for magnetic abrasive finishing,but few studies have been conducted on its dynamic characteristics.This article focuses on the motion trajectory of magnetic abrasive particles in the process of magnetic abrasive finishing and the difficulty of observing the finishing effect under different experimental parameters.Finite element software ANSYS Maxwell is used in combination with discrete element software EDEM to dynamically simulate the process of magnetic abrasive finishing and explore the impact of different experimental parameters on the finishing effect.The main research content is as follows:Firstly,the introduction of the magnetic abrasive machining technology for the inner surface of pipe fittings and the principle of discrete element method is presented.The physical model adopted by the discrete element method is determined based on the force situation of magnetic abrasive particles during the grinding process and the material removal mechanism of magnetic abrasive machining,which includes the Hertz-Mindlin with JKR contact model,standard rolling model,and wear model.In response to the problem that EDEM software cannot load magnetic field force,the C++ programming language is used to develop a dynamic magnetic field force model,enabling the application of the discrete element method in the field of magnetic abrasive machining.Secondly,the calibration of magnetic abrasive particle micro-parameters is conducted.By analyzing the impact of various micro-parameters on the simulation test results,the micro-parameters to be calibrated are determined.The training and testing set data required by the RBF neural network are generated using the Latin hypercube sampling method,and batch experiments are carried out to obtain corresponding response values.The required micro-parameters are determined by combining the pattern search method with the RBF neural network prediction model.Finally,discrete element simulations of the magnetic abrasive machining process are conducted to analyze the motion of magnetic abrasive particles and explore the influence of different angles of heteronymic magnetic poles and rotating magnetic field speeds on the efficiency of magnetic abrasive machining.The accuracy of the simulation results and the feasibility of numerical simulation analysis are verified by experiments.The research content of this article provides a reference basis for parameter selection in magnetic abrasive machining.By means of numerical analysis,difficult-to-observe factors such as the motion of magnetic abrasive particles and changes in grinding forces during the magnetic abrasive machining process can be deeply analyzed,which is of great significance for analyzing the machining mechanism.