CALCULATION OF HEAT TRANSFER BETWEEN THE CONTINUOUS-CAST INGOT AND THERMAL INSULATING DEVICE USING MATHEMATICAL MODELING
DOI:
https://doi.org/10.14529/met180213Keywords:
continuous casting machine, continuous-cast ingot, mathematical model, cooling, energy saving, heat exchange, heat of melt, temperature field, heat content, heat insulationAbstract
The article describes energy saving technology, which allows to increase the efficiency of fuel and energy resources use in the continuous casting of steel. It is proposed to use the heat of the melt of a continuously cast ingot, which will reduce or eliminate its heating before rolling. For this purpose, a mathematical model of rational cooling of a continuously cast casting in a continuous casting machine with the use of heat insulation in the air cooling zone was developed. Materials of a heatinsulating device and its constructive application in the technological scheme of CCM are described.
To calculate the heat transfer between the ingot and the heat insulating device, the problems of cooling the ingot and heating the heat-insulating structure are solved together. The thermal balance of the heat insulation zone was compiled. The interaction of heat flows between the ingot and the heat insulating device is analyzed using mathematical modeling.
Based on the simulation results, it can be concluded that when using the thermal insulation zone, the ingot solidification occurs at speeds up to 1.3 m / min. At higher drawing speeds, to fully solidify the ingot before cutting, it is necessary to increase the cooling intensity in the secondary cooling zone (SCZ). The average mass temperature increases by 160–260 °С. According to the data obtained, it can be concluded that when the thermal insulation is used, the ingot is thermostatted, the temperature difference between the surface and the center is reduced by 100–220 °С compared to air cooling, that is, the heat saving is about 30%.
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