Numerical representations for flow velocity and shear rate inside electromagnetically levitated droplets in microgravity

• DOI: 10.1038/s41526-019-0067-2
• Publication Date: 2019-03-25T11:03:11Z
• Authors: Xiao Xiao; Jonghyun Lee; Robert W. Hyers; Douglas M. Matson
• Keywords: Liquid metal

Electromagnetic levitation techniques are used in a microgravity environment to allow materials research under containerless conditions while limiting the influence of gravity. The induced advective flow inside levitated molten alloy droplet is key factor affecting solidification phenomena potentially influencing measurement thermophysical properties metallic alloy. It thus important predict velocity various operation during melt processing. In this work, magnetohydrodynamic model applied over range which electromagnetically droplets processed represent maximum and shear rate as polynomial function heating voltage, density, viscosity, electrical conductivity materials. An example given for ternary steel Fe-19Cr-21Ni (at%) demonstrate how internal advection different heater settings becomes strong temperature determining transition from laminar turbulent conditions. results directly applicable other with considered, including Ni-based superalloys, Ti-6Al-4V, many commercially-important alloys.