The study on ice thermal storage system is to improve total system performance in actual air-conditioning facilities. To obtain the high charging and discharging efficiency in ice thermal storage system, the improvement of thermal stratification is essential, therefore the process flow must be piston flow in the cylindrical type. In the charging process, in case of inlet flow rate the thermal stratification has a tendency to be improved with the lower flow rate and smaller temperature gradient.
The experimental results are as follows.
(1) In case of Thermal storage, the stable stratification is formed with 2LPM and 4LPM after τ=0.5 and the temperature of inlet brine rises. therefore because of the heat conduction effect of Ice Ball and delay of inflowing water mixing, the heat flow keeps stably till τ＝1.5.
(2) In case that the flow directions inside the thermal storage tank are the upward flow in charging and the downward in discharging, thermal stratification is improved because the thermocline thickness is maintained thin and the degree of stratification increases respectively.

• 이원섭(Member, Gangneung Wonju National University) | W. S. LEE Corresponding Author