In the visualization of metal solidification numerical simulation, when the sand casting solidifies gradually, to display the solidification state, it is only necessary to display the relative position of these non solidified grid nodes without determining their absolute position. Therefore, drawing the outline diagram of the outermost outline of the overall grid of sand casting can effectively display the simulation state and the solidification position.
The method to find the contour of sand casting is as follows: first, traverse all grids. If one of the six grid cells around a grid cell is not a sand casting grid cell, mark the grid, which is a boundary grid; Secondly, it is convenient for all the searched boundary grids to go to the grid, and judge the six grids around the grid. If the number of non sand casting grids is greater than two, the grid is the boundary contour grid for recording.
The grid searched above is displayed separately, that is, the contour of sand mold casting, as shown in Figure 1, the boundary contour of grinding ball casting, and as shown in Figure 2, the solidification state during solidification, that is, the display of isolated region. From the figure, it can be clearly seen that the isolated region of non solidified metal and its position in the whole sand mold casting.