Abstract:By reasonably controlling the flow field in the tundish, the inclusions in the molten steel can be promoted to rise and the composition and temperature of molten steel can be homogenized. Water model experiment and numerical simulation are two main methods to study the flow field in tundish, each of which has its own advantages and disadvantages and should complement each other. Numerical simulation is cheap and fast, but due to the uncertainty of boundary conditions and the limitation of turbulence model, it is difficult to fully reflect the flow field in the tundish. The model test can accurately simulate the flow field in the tundish, but it cannot accurately simulate the influence of temperature field, nodule, covering agent and blowing on the flow field in the tundish.The results show that the turbulence controller has a good effect on reducing the turbulent kinetic energy of the molten steel jet from long nozzle, homogenizing the temperature and compositions of the molten steel, diverting the liquid steel jet upward to reduce the volume fraction of dead zone, prolonging the average residence time and optimizing the flow field structure. The combination of turbulence controllers with weir, dam and diversion wall is better than that using single flow control device.The tundish flow field can be optimized and the inclusion removal can be promoted by reasonably adjusting the distance between the weir and the tundish bottom, the height of the dam, the distance between the weir and the dam, the distance between the weir and the outlet, the number, size and angle of the opening of the dam. The gas curtain wall improves the cleanliness of liquid steel. The annular gas curtain can solve the problem of low and unstable inclusion removal ratio with the strip gas curtain to improve the inclusion removal ratio. Finally, it is the trend that the mathematical model of tundish flow field is refined and the influence of more process and boundary conditions is considered. For the specific research of tundish flow field, the optimization index can be set pertinently to make the optimization work more efficient. As another important research technique of tundish flow field, water model experiment has been continuously explored and innovated in experimental methods and measurement principles for the purpose of improving experimental accuracy.
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