The main innovation of the research on the numerical simulation and application of sand casting molding process is that it is possible to use the classical numerical simulation theory as the guide and the advanced analysis technology as the means to solve the problems existing in the sand casting production process of enterprises and to use the special mold filling and solidification simulation for analysis and then call the ANSYS results for comprehensive analysis, It provides a direction for the application of self-developed numerical simulation software in engineering. The innovation points of the subject are as follows:

- Firstly, the problem of data transfer from the geometric model of sand casting established by Pro / Engineer to the numerical simulation software ProCAST is solved.
- Aiming at the sand mold casting defects of the flywheel currently produced by the enterprise, the casting simulation software ProCAST is used as a tool to simulate the filling and solidification process of sand mold casting, accurately reflect the actual situation of the filling and solidification process of sand mold casting, predict the possible sand mold casting defects and the positions where the defects occur. The research results show that the cold iron is placed near the hot spot of the sand mold casting, and the riser is placed at the last solidification position to make it solidify in sequence, It can effectively improve the hot spot state and achieve the purpose of eliminating and controlling defects. Moreover, the simulated flywheel sand mold casting can meet the quality requirements after the actual inspection, which proves that the sand mold casting process optimized by the numerical simulation technology is effective and feasible.
- Based on the thermal elastic-plastic model, the stress field of sand mold casting after solidification is simulated by using the large-scale general finite element software ANSYS, and the interface flow between the finite element software ANSYS and ProCAST is established based on the thermal stress coupling technology and the influence of phase transformation expansion and sand mold obstruction on the stress of sand mold casting.