Modeling of an ice-on-coil thermal energy storage system

Abstract

Stand-alone analytical models were developed for an ice-on-coil thermal energy storage (TES) system for both charging and discharging modes. This paper describes the basic heat transfer analysis and presents the characteristics of the charging and discharging modes determined from the model. The output results of the cooling charge model were the volume of ice in the TES tank and the cooling charge rate. Error analyses of the ice volume and cooling rate indicated that the model predictions were within 5 and 12%, respectively, of the experimental values. A factorial design sensitivity analysis was conducted to show that the variable T f - T max and the interactions ( T f - T max) × h o, h i × F, and h i × h o × F had significant effects on both the cooling charge rate and the ice radius. The output results of the cooling discharge model showed that the tank bulk water temperatures were within 5% of the experimental values. The sensitivity analysis showed that the variables h o and T ci, as well as the interactions m ̇ × % ice × T ci and m ̇ × h o × % ice , had significant effects on the bulk water temperature. Although the models involved various assumptions, the results were considered helpful for the design and understanding of the evaporator/ice storage tank.