Abstract
The pinch force which is one of the most general electromagnetic forces in the metallurgical field can be generated by impressing an electrical current in a liquid metal.In this force field, electrically nonconductive particles suspended in a liquid metal will receive a force in the opposite direction to the pinch force, and be squeezed out from the liquid metal.
In the present study, this principle was applied to the separation of nonmetallic inclusion particles from liquid steel.The separation efficiency η of inclusion particles from a circular pipe flow of liquid steel was thought to be a function of the following nondimensional pararneters:VR(=Vpt/Wm), C1(=μeIrms2/ρν2), DR(=dp/2r1), Re=(r1wm/ν), Z=(z/r1), and r1/δ.The plug-flow model and the particle-trajectory model were used for calculating η. The results obtained by both models showed that η was a function of VR, (CIDR2/Re)Z and r1/δ. The particle-tralectory model showed a srnaller value of η than the plug-flow model.The value of η calculated by the former model increased with increasing(CIDR2/Re)Z and decreased with increasing VR. Although η did not change with r1/δ when r1/δ<1, it decreased gradually with increasing r1/δin the region ofr1/δ>1.
The values of η for a channel induction heater installed in a continuous casting tundish were estimated to discuss the practicability of the present inclusion separator.It was found that η was greater than 95% for inclusion particles with the diameter greater than60μm.
