Fluid Flow and Heat Transfer in a Tundish with Channel Type Induction Heating

Abstract

Because of the high heating efficiency, channel type induction heating is utilized in the tundish in order to reduce the temperature fluctuations of the molten steel in the process of continuous casting. In order to have a deep insight into the complex MHD (magneto hydrodynamic) process in the tundish with channel type induction heating, water model and mathematical model are performed to describe the fluid flow and the heat transfer in the tundish. A non-isothermal water model with channel heater is built to investigate the thermal convection in the tundish. The electromagnetic force and Joule heating are introduced into the momentum equations and the energy conservation equation as a source term, and the coupled flow and temperature field are solved by the finite volume method. The results show that the predicted flow field and temperature field agree with the experimental data. In the case of channel type induction heating, there are two spiral flow in the channel due to electromagnetic force, and the temperature difference of molten steel is 12 C between the inlet and the outlet of the channel due to Joule heating.

Numerical Simulation of Collision-Coalescence and Removal of Inclusion in Tundish with Channel Type Induction Heating

“…2. Part I is about the electromagnetic field, 24) part II is about the flow field and temperature field, 25) and part III is about the collision and coalescence among the inclusions in molten steel. The calculation procedure is as follows.…”

“…It need no repetition in here. 24,25) In the mathematical model, Joule heating (σ J 2 ) acts as the source term in the energy equation, it increases the temperature of molten steel in the tundish, and related the thermal buoyancy (β (T 0 − T) ρ f g) change the fluid flow. The electromagnetic force (J B)   × acts the source term in the momentum conservation equation, it stirs the molten steel in the tundish.…”

“…The other boundary conditions about electromagnetic field, fluid field and temperature field can be found in our previous paper. 24,25) Diffusion and convection are two mechanisms for inclusion's transport in the molten steel. Thus, the inclusions flux at the tundish boundaries (top slag, bottom wall, incline wall and channel wall) can be expressed by the convection flux and the diffusion flux.…”

“…The predicted magnetic field, fluid field and temperature field have been validated in the previous paper. 24,25) Certainly, the inclusion size distribution should also be validated. Figure 5 shows that predicted value of inclusion number density agrees well with the experimental data when the inclusion diameter is less than 15.5 micro at the ladle shroud and 21.21 micro at the tundish exit.…”

Flow Field, Temperature Field, and Inclusion Removal in a New Induction Heating Tundish with Bent Channels

“…They found that there was a significant effect of electromagnetic force on the molten steel flow in the tundish, and that the flow pattern varied with Joule heating, while the electromagnetic force had little effect on it. Yang et al [10,11] established physical and mathematical models to investigate electromagnetic phenomena, flow field, and heat transfer in a channel type induction heating tundish. Results showed that in the induction heating channels, the electromagnetic field, current field, electromagnetic force, and heating power are the greatest.…”