• Proceedings of the KSME Conference
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• 2001.06d
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• pp.280-285
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• 2001

This paper presents a modelling of thermal discharge performance for a static ice-on-coil ice-storage tank. Through the present study, discharging characteristics were examined with the existing results of theoretical and numerical heat transfer analyses. Also, an experiment was conducted to obtain a real set of discharge performance. The thermal effectiveness, the ratio of the actual heat transfer rate to the maximum possible heat transfer rate, decreased when the stored energy decreased during discharging period. And the effectiveness increased as the coolant flow rate through the storage increased, of which increasing rate decreased abruptly near the maximum and the minimum stored energy. An empirical correlation was obtained from the experimental and the numerical analysis data.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.25 no.11
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• pp.624-630
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• 2013

A truck refrigeration system using phase change material (PCM) is expected to have a lower noise level, reduced energy cost, and much lower local greenhouse gas emission. Recently, a forced convection type PCM refrigeration module has been developed. As the operation time increases, the PCM around the air inlet melts, because of a large temperature difference between the PCM and air. Therefore, the latent heat transfer area decreases and the heat transfer rate of the module decreases even though there is a lot of PCM which does not melt around the air outlet. A computational fluid dynamic modeling of the PCM refrigeration module was developed and validated by the experiment. Using the CFD, the design parameters, such as the mass flow rate of the air and roughness of the slab, were investigated to improve the heat transfer inhomogeneity. As a result, the adoption of partial roughness on the slabs improved the heat transfer inhomogeneity and reduced a fan power.

• Korean Journal of Air-Conditioning and Refrigeration Engineering
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• v.12 no.4
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• pp.337-344
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• 2000

The present study describes a one-dimensional modeling of encapsulated ice storage tanks. The thermal transmittance of capsules in this model uses the results from the Arnold's experimental $study^{(2-3)}$.In this model, ice storage tank is partitioned by several control volumes for the analysis, each having same number of capsules. The model is validated by the comparison of the measured data from an ice storage tank installed at a building with the capacity of 1200 ton-hrs and the simulated results with the same inlet brine temperature conditions into the tank.

• Proceedings of the KSME Conference
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• 2001.06d
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• pp.298-303
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• 2001

A fundamental study on the under water harvest-type ice storage system and its temperature characteristics in ice storage system was performed experimentally. The experiments were conducted by changing the inlet refrigerant temperature of an evaporator to analyzing the thermal fluid motion inside the ice storage tank. From the experimental results, the cold storage characteristics were investigated by measuring the axial and radial temperature variations inside the ice storage tank with respect to the inlet and outlet refrigerant temperatures of an evaporator. In case of the under water harvest-type ice storage system, thermal fluid. motion inside the ice storage tank was shown differently in comparison with that of other ice storage systems. During the cooling storage process, there was no supercooling phenomenon in the ice storage tank. These results show the characteristic of this system and the possibility of application to other fields.

• Journal of Energy Engineering
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• v.16 no.4
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• pp.164-169
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• 2007

The decrease in the summer peak electric load in our country is very important. The government has arranged and implemented a lot of support policies and statutes to decrease the peak electric load. And the ice-thermal-energy-storage system is known as one of the alternatives. The purpose of this paper is to evaluate the performance and the total efficiency of its storage tank, conducting the charging operation, the parallel operation and the single operation of a storage tank. The thermal energy density stored and discharging efficiency of a storage tank and the efficiency of total energy utilization of system are $18.4\;USRT-h/m^3$, 96.2% and 2028.7 kcal/kWh under the operation of design condition. When the storage tank is supplied more ice thermal energy than design condition, it is estimated that the efficiency of system are lower than the design condition by the supercooled effect.