Prediction of misrun formation via STAR-Cast

The prediction of misrun formation is based on STAR-Cast’s unique, fully-coupled computational continuum mechanics approach, featuring a multiphase mold filling module. Only this combination can enable concurrent computation of fluid flow, temperature and liquid-solid transition.

Left: Temperature evolution on the metal surface during mold filling of a turbine blade featuring an extremely thin trailing edge.

Right: Flow velocity on the metal surface during mold filling for the same blade geometry.

This misrun prediction includes a permeability calculation for the mushy zone, which is treated as porous media: the Darcy term in the momentum equation depends on the permeability of the mushy zone; the fraction liquid curve and the secondary dendrite arm spacing are the alloy-specific input parameters. Particularly in the case of thin-walled castings, STAR-Cast is able to provide enhanced enmeshment techniques to ensure exact results.