This paper presents a comprehensive numerical investigation of the influence of cooling conditions on base separation, void formation, and thermally induced stresses during the solidification of a high Prandtl number energetic melt in a cylindrical enclosure. Numerical models have been developed to simulate the heat and mass transfer processes in melt casting as well as analyze the base separation and thermal stresses induced during solidification. Two models are dynamically coupled, and the numerical predictions are validated against experiments. Based on the numerical analysis, modified cooling conditions are suggested that are shown to reduce base separation.