Abstract
This study focuses on a water circulating-type snow cooling system in which water flows through the bottom layer of the snow. The characteristics of heat exchange between the snow and water were investigated experimentally under the following three different snow storage conditions; 1) laboratory-sized snow stored in a 0℃ room for 0 to 15 days, 2) snow stored in a 12-ton reefer container for about 4 months, 3) snow stored in an 150-ton storage in the actually operated snow cooling facility for about 4 months. The surface shape of the snow and inlet/outlet water temperatures of the heat exchange section were measured at proper time intervals. Regarding the change in shape of the snow, phenomena such that there was almost no change during a certain period, the open crack occurred in the snow and the snow lump suddenly subducted were observed. The outlet water temperature varied according to the phenomena. How the crack occurred differed somewhat according to the snow storage conditions. The heat exchange performance between the snow and water decreased with the snow storage periods. The decrease clearly appeared even in 1 day. The ratio of the water temperature drop due to heat exchange with the snow to the temperature difference between the pump-feeding water and the snow varied with the water-flowing direction length of the snow at the initial and a given time, the gap length between the snow and the side wall, and the snow storage period.
