Determination of Transient Flow Pattern in Steel Continuous Casting Molds Using Nail Board Measurement and Onsite Top Flux Observation

In the current study, the transient fluid flow pattern in steel continuous casting molds with varied dimensions was evaluated using nail board measurement and onsite top flux observation. Effects of steel throughput, argon flow rate, submergence depth of the submerged entry nozzle, and mold dimension on the flow pattern inside the mold were investigated. The top flux under lower steel throughput, higher gas flow rate, and shallower submergence depth of the submerged entry nozzle were easily swept away by argon bubbles so that the molten steel was exposed to the air, called exposed eyes. Linear fitting equations between the steel throughput and the gas volume percentage for the transient flow pattern were performed. The critical linear relationships of the double roll flow pattern transformed to the complex flow, and the complex flow transformed to the single roll flow pattern. Flow pattern regimes were plotted with the results of the industrial measurements. The present work aimed at providing an operating interval of the steel throughput and the gas volume percentage to maintain the double roll flow pattern inside the mold for the regular casting practice.