HEAT TRANSFER IN A CYLINDRICAL CRUCIBLE WITH LIQUID METAL IN ITS ALTERNATE EXPOSURE TO TRAVELING AND ROTATING MAGNETIC FIELDS

A description is given of experimental investigations of the process of heat transfer in a cylindrical container with liquid gallium in its alternate exposure to traveling and rotating magnetic fields. In the experiment, we created the process of two-directional electromagnetic MHD-stirring of liquid metal similar to the process of stirring in the hot top of the crystallizer of a continuous casting machine for round ingots from aluminum and its alloys. To control the front of directed crystallization of the ingot, the flow must be symmetrical with respect to the longitudinal axis. In the experiment, we implemented an alternate exposure to traveling and rotating magnetic fields ensuring such symmetry of the flow being generated. Heat was transferred from the heater on the alloy surface to the thermostated bottom of the container. In the experiments, thermal measurements were used to investigate heat transfer in the container in the direction of its vertical axis, and also estimates were made of the time of stirring the introduced impurity at various regimes of MHD-stirring of liquid metal. It has been found that the heat transfer eff ect is best ensured by poloidal flow, but the creation of additional azimuth flow signifi cantly decreases this eff ect. It has been found that in alternate exposure of liquid metal to traveling and rotating magnetic fields, the heat transfer effect occurs in a way similar to traveling and rotating magnetic fields acting on the metal simultaneously and continuously.
   
Author:  S. Yu. Khripchenko
Keywords:  semicontinuous cylindrical ingots, two-directional MHD-stirring, experiment, heat transfer, stirring time, alternate regime
Page:  1126