Karman vortex probe for the detection of molten metal surface flow in low velocity range

A previously developed Karman vortex probe is equipped with a circular cylinder for the generation and detection of Karman's vortex streets. This probe is known to be useful for the measurement of the meniscus velocity of molten steel flow in the real continuous casting mold. The detectable velocity ranges from approximately 10 to 70 cm/s. Efforts were devoted in this study to develop a Karman vortex probe capable of measuring a meniscus velocity lower than 10 cm/s. Three kinds of non-circular cylinders were selected to detect the shedding frequency of Karman's vortex streets in this low velocity range. A triangular cylinder was found to meet this requirement provided that the direction of flow approaching the cylinder is known a priori. Accurate measurement was possible for a minimum approaching velocity of 5 cm/s.