Development and calibration of a Karman vortex probe for measurement of molten-steel velocities

A velocimeter called the Karman vortex probe was developed to measure the velocity of molten-steel flow near the meniscus in continuous-casting molds. The measurement principle of this probe is based on a linear relationship between molten-steel velocity and the shedding frequency of Karman's vortex streets, which are formed behind a circular cylinder immersed in the molten-steel flow field. Calibration of the probe was made in the absence of, and in the presence of, mold powder. The adequacy of the presently developed Karman vortex probe was verified partly by comparing the molten-steel velocity data measured in actual continuous-casting molds to those obtained using a water model with the same shape and size as the actual mold. The meniscus-flow velocity in the absence of electromagnetic braking increased and then slightly decreased with an increase in the casting speed.