Filling And Solidification Of Squeeze Casting Based On SPH Method Process Numerical Simulation Research

Squeeze casting,also known as liquid die forging,is a process between casting and forging.It has the advantages of casting and forging at the same time,becoming a near-net-forming technology with little or no cutting.Using computer technology to simulate the flow of molten metal in the squeeze casting cavity,you can more intuitively observe the flow of molten metal and its temperature change process,and predict the defects that may appear in the squeeze casting,and help technicians based on the existing The problem is to improve the structure and process design of extrusion castings in order to obtain qualified extrusion castings and improve product quality and production efficiency.Therefore,the numerical simulation of the filling process,temperature field and solidification process of squeeze casting is of great significance to the reasonable selection of process parameters.At present,although the development of numerical simulation based on the grid method is relatively mature,there are still many shortcomings.For example,the finite element numerical simulation method cannot handle large-scale deformation well.Smooth Particle Hydrodynamics(SPH)method can solve this kind of problem well.This paper firstly establishes a three-dimensional mathematical model based on the SPH method,and then independently writes a C++ program.Finally,a good numerical simulation of the squeeze casting filling process and solidification process is carried out,and compared with the finite element and experimental results,there is a good consistency.The specific research content is as follows:First,establish the overall calculation framework of the squeeze casting process based on the SPH method numerical simulation,and explain the theoretical ideas and basic equations of the SPH method.In this paper,Open MP technology is written into the program,which realizes parallel calculation,greatly shortens the calculation time,improves the calculation efficiency,and establishes a program model using C++ computer language.Secondly,a three-dimensional squeeze casting filling process mathematical model based on the SPH method is established,and the squeeze casting filling program is independently written in C++ language.Firstly,numerical simulation is performed on the classic example of dam break,and the simulation results are compared with the experimental results in the literature,and a good consistency is obtained.Then the dam break with obstacles was simulated,which better demonstrated the complex flow process of liquid based on SPH method.Finally,the filling process of the squeeze casting wheel hub is simulated,and the temperature distribution at the end of filling is compared with the result of the finite difference method,which is basically the same.Finally,a mathematical model of the solidification process of three-dimensional squeeze casting based on the SPH method is established,and the squeeze casting solidification program is written in C++ language.First,by numerically simulating the heat conduction problem of the flat plate in the classic example,and comparing the simulation result with the analytical solution,a good agreement is obtained,which verifies the calculation result of the temperature field of the program built in this paper.Secondly,this paper uses the temperature rise method to simulate the latent heat of cylindrical castings,and numerically simulates the filling process and solidification process of the convex parts of squeeze castings.Compared with the finite element and experimental results in the literature,they are in good agreement.Sex.