Numerical Simulation Of Mould/billet Temperature And Concentration Field In The Continuous Casting Of Round Billet

High quality billets are obtained from the suitable control of solidification processing and structure, for solidification structure is one of the key factors in forming the properties of billets. During the processing of steel continuous casting, heat flux and concentration distribution in the mould and billet have significant effects on the processing operation and billet's quality. The formation of stick breakout, crack and segregation comes out due to the abnormal heat flux and concentration between the shell thickness and mould, which makes it more important to detect the heat flux in the mould. For the limited methods of detection, in the local processing, it's not only difficult to observe the process of steel solidification in the mould, but also not economical and sufficient to do experiment study and industrial trial on it. So, in this paper, a simulate model has been developed for the study of steel solidification behavior in the mould of continuous casting.In this paper, on the one hand, the distributions of measured temperature and heat flux along the height of round billet mould are studied, as well as the heat flux around the perimeter, which based on the data of continuous monitoring temperature in round billet casting machine. The paper also discussed the influences of casting speed, carbon content, EMS, powder and pouring temperature on the average temperature and heat flux, which provide a basis for making heat flux as an important detecting parameter in the process of the continuous casting.Data analysis indicate: Higher casting speed leads to increase the average mould heat flux, particularly more at higher carbon content; Molten steels with higher carbon content had higher average heat flux along the mould, as well as higher perimeter fluctuation at 2L; The average heat flux lengthways changes to different powder types. Pouring-temperature has little effect on the heat flux and usually changes with the other parameters in order to keep the heat flux steadily.On the other hand, a three-dimensional transient heat-transfer model has been built up to simulate the temperature field and the distribution of heat flux in the continuous casting of round billet. Meanwhile, based on the exactly calculation of temperature field, a solute diffusion model has been developed for the calculation of solid fraction and concentration field, as well as the shell thickness. The effects between processing parameters and shell thickness also have been discussed.