SOLIDIFICATION OF ARBITRARILY SHAPED CASTING IN MOLD CASTING SYSTEM

In the present investigation, an enthalpy formulation is applied to the solidification process of an arbitrarily shaped casting in a mold-casting system. The effect of thermal contact resistance existing at the mold-casting interface is also studied. All of the computations are performed on a Cartesian coordinate system without recourse to coordinate transformation or grid generation for the arbitrary shape of the mold-casting interface. A single region method based on the weighting function scheme is found to solve this mold-casting conjugate heat transfer problem quite efficiently. A few cases are conducted to study the effects of the Stefan number, the thermophysical properties and the thermal contact resistance (at the mold-casting interface) on the solidification processing. The numerical result of the moving solidification front is investigated for each case. To examine the performance of the present numerical technique in a particular respect, chill blocks are employed at some locations inside the mold such that more than one isolated liquid region could exist in the casting during the solidification processing. Even for such a 'multiple-region' problem, the present numerical method shows good performances. No additional computational effort is needed as compared with the cases without chill blocks.