Physical And Numerical Simulation Of Flow Characteristics In Five-strand Tundish For Continuous Casting

This paper is divided into two parts.In the first part,the flow field of molten steel in tundish of five-strand continuous casting in a factory is studied by physical simulation.The parameters of stagnation time and dead zone ratio are investigated,and then the optimal design scheme of tundish flow control device is put forward.In the second part,based on the optimization scheme,a numerical model is established to analyze the effects of reducing the pulling speed of each flow,closing one flow,two flow or other conditions on the flow characteristics of multi-flow tundish.And the influence of increasing long-current casting speed on dead zone on the basis of constant or increasing total pass steel quantity.The experimental results show that:(1)The flow characteristics of the prototype tundish are quite different from those of the near and far flows,and there are serious short-circuit currents,short actual average residence time and large dead-zone ratio.(2)After the optimization of retaining wall and flow control device,the flow characteristic parameters of tundish flow field have changed greatly.The actual average residence time and stagnation time of molten steel in tundish have been greatly improved.At the same time,the proportion of dead zone and piston zone has been greatly improved,and the proportion of dead zone has been reduced by about 47%,while the proportion of piston zone has been enlarged by four times.(3)Based on the optimal scheme obtained by the water model,the numerical simulation method was used to study the production reduction operation.It was found that the overall flow characteristics of the tundish with the closure of the second and fourth runners were the best,the dead zone volume was smaller,and the flow difference between the two runners was the smallest.(4)With the increase of total steel throughput and the same situation,increasing the long-flow casting speed can reduce the dead zone ratio and the flow difference of each flow,while the short-circuit flow has no significant change under the same total steel throughput.