Numerical simulation of the directional solidification process with multi-shell mold being gradually immersed in water

Abstract

In order to improve the heat insulation effect, a multi-shell mold structure can be applied in directional solidification. As this kind of mold is gradually immersed into water, higher temperature gradient will be formed between the upper and the bottom of a casting, which promoted the directional solidification of the casting. This process was simulated, in which the convection and radiation heat transfers inside the multi-shell structure was considered. The insulation effect of the multi-shell structure was obtained with comparison with dense mold and single layer shell mold. The uprising scheme of the water level was discussed to achieve stable and minimum height difference between the water level and the solidification front and almost flat solidification front can be realized. The simulation results were verified by casting experiment.