Production Behavior of Slush Ice on a Rotating Vertical Cooled Tube

摘要

An experimental and analytical study has been performed to investigate the production behavior of slush ice by use of an oscillatory rotating cooled tube which was installed vertically in a test vessel fil1ed with ethylene glycol solution. Experiments were carried out under a variety of conditions, such as angular acceleration of the cooled tube, rotation angle, cooled wall temperature, and the initial concentration of solution to determine the production performance of slush ice. It was found that a thin frozen layer which was formed on the cooled tube was continuously separated from its surface depending on the operation conditions, and as a result, a large amount of fine ice crystals were produced in the test vessel. The operation range in which the continuous production of slush ice was identified experimentally. Furthermore, an analysis was made to determine the characteristics of ice packing factor (I. P. F.) by use of an one--dimensional heat transfer model. The range of initial concentration of solution was determined where the tendency of the analytical results and experimental ones agreed well.