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With the development of computer hardware, numerical simulation of casting process has made rapid progress. The commercial software packages of casting process simulation, therefore, have become more and more practical. This paper introduces both the basic route of numerical simulation of casting process and the current developments of InteCAST software, a commercial numerical simulation software package of casting process. The mathematical model and some techniques, such as nonuniform elements technique, improved equivalent specific heat method, are introduced. Finite difference method is adopted for the simulation of mold filling and solidification process; the mold filling simulation is based on the SOLA-VOF method. The FDM/FEM integration method and FDM are employed for the simulation of stress field. The routes of these two methods and some simulation results are given respectively. Nonuniform elements technique, which employs fine elements for the boundary of different materials and coarse elements for the inner, can reduce the computational time greatly. The improved equivalent specific heat method, equivalent specific heat method with a pseudo solidification range for pure metal and integrated temperature emendation, is employed to deal with the latent heat, which can not only simplify the program but also save the memory and disk space.Then, three applications are given. The first one is about optimizing the riser system of steel casting. The process of ductile cast iron casting is analyzed secondly. Finally, the fluid flow sequence of gray cast iron is discussed. These applications show that the software can help technologists optimize casting process by forecasting the entrapped air and entrapped slag defects occurrence during mold filling process and shrinkage defects occurrence in the following solidification process.

A new technique for thermal field simulation of castings using a non-uniform elements method based on Finite Difference Method (FDM) is proposed. It is an improvement on the uniform elements method, which is now used in our modelling software package. In this new method, the elements in the casting/mould system are classified into two types—coarse and fine. Assumptions and principles used to distinguish coarse and fine meshes, together with the flow chart of the algorithm and a 2-D example, are given. 3-D FDM heat conductive equations of two types of mesh are deduced. The technique has been applied in practical simulation and an example is presented. Calculated results are in good accordance with practical production and those from the uniform elements method, but computing time is greatly shortened. So this non-uniform elements method has good prospects for future application and can be of benefit to the Computer Aided Engineering (CAE) technology used in the foundry industry.