Conditions for all simulations:

• The domain is rectangular (5 cm wide and 15 cm high) (except Case 3)
• Both sidewalls are adiabatic and the top and bottom walls are cooled by ramping down their temperatures. This creates the following casting conditions:
• casting speed: V=10 cm/hr
• temperature gradient: G=20 K/cm (i.e., the top is 300 K hotter than the bottom)
• cooling rate: Tdot=VxG=200 K/hr

Movies:

• Case 1: Original CMSX2 composition (65.8%Ni, 8%Cr, 5%Co, 1%Ti, 6%Ta, 5.6%Al, 0.6%Mo, 8%W)
• Mixture concentration of Ti
• 3 fragments (100, 200, and 500 microns) advected out of a freckle and remelting (only the 500 micron fragment survives and causes a grain defect)
• Case 2: Modified CMSX2 composition (decreased Ta to 1%; increased W to 13%)
• Mixture concentration of Ti
• Case 3: Expanding Domain (lower half: 2.5cm wide; upper half: 7.5cm wide), Original CMSX2 (for a uniform width of 5cm, no freckle is predicted!)
• Mixture concentration of Ti