1.Establishment of finite element model
The sand casting process of hydraulic turbine blade is simulated and analyzed by ProCAST software. Because there is no solid modeling function in ProCAST software, the three-dimensional solid modeling of blade is completed in UG; The three-dimensional solid modeling of riser, gating system and sand box of hydraulic turbine blade sand casting is completed in Pro / E. Complete the assembly of blade sand mold casting, riser, gating system and sand box in Pro / E to form a complete casting system, then output IGES format file and import meshcast module in ProCAST software for meshing.
Tetrahedral grid elements are used for division. The sand casting grid is dense and the mold grid is sparse. The whole sand casting system model includes 1161488 volume grids and 219756 nodes.
2.Definition of material
The material of sand casting of water turbine blade is ZG00Cr13Ni4Mo, and the sand mold is sodium silicate sand.
3.Setting of initial and boundary conditions
It is defined that the pouring temperature of blade sand casting is 1565 ° C, the pouring time is about 230s, and the initial temperature of sand mold is 20 ° C. The thermophysical parameters of blade sand casting and the interface heat transfer coefficient of casting mold are selected in the established database.