| Induction heating technology in the continuous casting process can effectively compensate for the tundish heat loss,better removal of inclusions.Meanwhile,the molten steel in the channel produces the phenomenon of cross section shrinkage under the action of electromagnetic force.The actual production needs to exert the pinching effect as much as possible to avoid the negative effect.In this paper,the dual-channel tundish was taken as the research object,and the distribution of the flow field and the temperature field in the tundish under the thermal buoyancy was comparatively analyzed.Using ANSYS to calculate the electromagnetic force and Joule heat in the tundish,it is introduced into the momentum and energy equations.Based on the finite volume method of OpenFOAM,the influence of induction heating on the thermal field distribution of molten steel flow was compared and analyzed,and the influence of channel diameter on the thermal field distribution of molten steel flow in tundish under induction heating was discussed.Based on this,the force analysis of molten steel at the near wall of the tundish channel based on the volume force and surface force of the deformable fluid is deduced,and the formula of the wall support force obtained by the molten steel is deduced.The effects of power,frequency,channel diameter and inlet velocity on the pinch effect of molten steel in the channel were discussed.(1)Thermal buoyancy has a great influence on the distribution of the flow field of molten steel.(2)No induction heating,the molten steel temperature from the injection chamber to the distribution chamber gradually decreased,the outlet temperature decreased 8K,induction heating,the direction of the temperature gradually increased,the outlet temperature increased 40K,induction heating steel temperature compensation significantly.(3)When induction heating is applied,the molten steel in the tundish is injected into the chamber under electromagnetic stirring to form two vortexes.The distribution chamber forms three vortices.The molten steel in the channel not only rotates in the radial direction but also forms three small whirlpools in the axial direction.This flow pattern is more conducive to the temperature uniformity,the molten steel flow path within the tundish longer,contribute to the removal of inclusions.(4)Under the same conditions,the molten steel enclosed in the channel by the iron core is more likely to appear on the molten steel wall than the molten steel enclosed by it.(5)At different power,frequency and inlet velocity,the distribution of supporting force of molten steel in the whole channel is similar,the supporting force on each circle has the same trend,and the strongest pinch effect is at 5π/24 arc,the weakest point is located at 3π/8,the critical point at which the molten steel separates from the wall almost unchanged.(6)Under different channel diameters,the change tendency of the wall support force of the molten steel in the whole channel is similar.With the increase of the channel diameter,the separation area of the molten steel and the wall is smaller. |
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