Ice melting characteristics of an ice thermal storage container filled with harvest ice

摘要

This paper deals with ice melting characteristics of an ice thermal storage container filled up with harvest ice. The change in outlet water temperature and its stability over time are examined when the position of the inlet pipe in the ice thermal storage container, the time taken for the water in the container to be replaced once, and the method of spraying water into the container are changed. The following results were obtained for the harvest ice thermal storage container : (1) Outlet water temperature in the ice thermal storage container is influenced by the position of the inlet pipe that is, when the water from the inlet pipe flows slowly through the ice packed bed, the lower outlet water temperature is able to be supplied to a heat exchanger for a longer time. (2) When water is sprayed from above the container, the outlet water temperature change against the non-dimensional time is represented by one correlation curve even when the water replacing once in the container is changed, and the outlet temperature stays under 2℃up to a non-dimensional time of about 0.8. (3) When water is sprayed from above the container, total heat release rate is also represented by one line. (4) Period of time during which the outlet temperature remains under 2℃is proportional to the time taken for the water in the container to be replaced once for three types of ice thermal storage in this experiment are used. (5) Heat transfer coefficient and modified Stanton number defined by volume flow rate are useful parameter for representation of ice melting characteristics.