A numerical simulation and analysis of the discharge characteristics and heat transfer performance during the ice-storage system

Abstract

During the ice melting process of the external ice-melting ice storage system, there is uneven ice melting in the different height of the ice layer, which directly affects cold discharge characteristics. Reasonable water flowrate of the distributor can improve cold discharge characteristics. A 3D dynamic mesh model was built using the computational fluid dynamics (CFD) method, phase change interface movement with time was tracked. And the ice-water heat transfer characteristics at different heights were analyzed and the influence of water distributor's flowrate ice-water mixture heat transfer performance and cold discharge characteristics during ice-melting process were also explored. The results showed that the ice layer above 30 mm height, The Nusselt number of water space averagely increased 23.8 % when the height had 5 mm increment. When the water flowrate increased by 0.01 g/s, the average Nusselt number of the water space increased by 6.7 % and the water outlet temperature increased by 12 % on average. Though the increasing of water flowrate can improve the convective heat transfer between ice and water, it also resulted in the standard temperature deviation and water outlet temperature increase. Under the premise of satisfying the cooling load, the water flowrate of the distributor should not be excessive.