Computer numerical simulation generally includes the establishment of geometric model, meshing, pretreatment (determination of initial conditions and boundary conditions), numerical calculation, processing of calculation results and so on. Before numerical simulation calculation, it is necessary to use CAD software to conduct three-dimensional modeling of crankshaft casting and mold. Generally, the CAD software used includes Pro / E, UG, SOLIDWORK, etc.
After geometric modeling, the model is divided into grids according to the calculation needs, which is divided into a large number of elements or geometric bodies composed of elements, which is conducive to providing corresponding data for other program modules. Mesh generation is mainly divided into finite element method, finite difference method and boundary element method. There are relatively few commercial software using boundary element method.
On the basis of finite element or finite difference mesh generation, the material is given thermophysical parameters, loaded with boundary conditions and initial conditions, the temperature field and flow field at each time of flow and solidification process are calculated, and the data are stored in the form of files to analyze the location of casting defects such as shrinkage porosity, shrinkage cavity, insufficient pouring and air entrainment. Based on the theoretical research of crankshaft casting process, many countries have developed commercial software for crankshaft casting process simulation, such as technalysis and flowscience in the United States, magma in Germany, ProCAST in France and Huazhu CAE developed by Huazhong University of science and technology in China, which can meet the general needs of crankshaft casting simulation.
The three-dimensional modeling of crankshaft casting and mold is adopted, and ProCAST is used to simulate and calculate the flow field and temperature field of crankshaft casting process, and predict the location of possible casting defects.