Vortex Formation and Chaotic Fluiddynamic in Continuous Casting Mould

摘要

The problem of steel vorticity in continuous casting mould is related to not-steady flow pattern. In some cases, it varies, in a cyclic manner, and this oscillatory behavior of flow pattern is cause of waves formation on meniscus. The presence of this problem was confirmed by Centro Sviluppo Materiali's mould cold model tests on different SEN (Submerged Entry Nozzle) configurations. The necessity to comprehend th ecauses of theat brings to a theoretical study of the phenomenon, based on analysis of non-linear nature of Navier-Stokes equations and their "chaotic" behavior. The risk of oscillatory pattern starting was found to be related to particular geometric and casting conditions in the mould. Moreover, analysis of mould temperature and level height data from plant was performed, to forecast anomalous situations. The new mdoel developed by CSM allows to forecasts if a configuration of casting conditions is particularly dangerous or not for flow pattern oscillation, and which period can be expected. Also techniques to evaluate the presence of this behavior from plant data have been developed.