Study On The Surface Formation Mechanism Of Abrasive Flow Polishing Elbow Surface Based On Large Eddy Simulation

Elbow and channel parts are widely used in industrial production.In pharmaceutical,food,aerospace,military and other fields the surface quality of the parts often have higher requirements due to its special use.The traditional machining method is difficult to finish the inner surface of small diameter elbow parts effectively,owing to its special structure.Abrasive flow machining is a kind of surface polishing technology which is not limited by the structure and size of parts.A lot of experiments show that abrasive flow machining technology can effectively improve the surface quality of parts.Therefore,the study of abrasive flow polishing technology has very important engineering application value and academic significance to improve the performance of elbow parts.In this paper,based on the numerical analysis method of large eddy simulation,the flow distribution of abrasive flow in the elbow separately is studied from the aspects of dynamic pressure,wall shear force,the flow state of abrasive particle flow at different cross section,vortex formation,particle flow trajectory by building the liquid-solid two phase flow numerical model.,study on the mechanism of surface formation of abrasive flow machining of polishing elbow with the flow distribution of abrasive flow.The influence of abrasive flow machining technology on the polishing quality of elbow parts is analyzed under different performances and different processing conditions.The influence of inflow angle,inlet velocity and elbow's own structural characteristics such as bend diameter ratio,bending angle,cross-section change form on the polishing quality of elbow parts is discussed.The fluid solid coupling method is used to transfer the numerical results of the fluid field to the workpiece,and analyzed the mechanical deformation of the elbow in the process of machining.Finally,the performance of abrasive flow machining of polishing elbow was tested by abrasive particle flow polishing test.