• 한국태양에너지학회 논문집
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• 제22권2호
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• pp.11-17
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• 2002

This paper is concerned with the development of a new method for making, separating ice and storage floated ice by installing an evaporation plate at under-water within a storage tank. In a conventional harvest-type ice storage system, a tank saves ice by separating an ice from an installed evaporation plate, which is located above an ice storage tank as an ice storage system. Developed new harvest-type method shows good heat transfer efficiency than a convectional method. It is because the evaporation panel is directly contacted with water in a storage tank. Also, at a conventional system a circulating pump, a circulating water distributor and a piping are installed, however these components are not necessary in a new method. In this study ice storage systems are experimentally investigated to study the charge and discharge of thermal energy. The results show the applicable possibility and performance enhancement of a new type.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 추계학술대회논문집B
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• pp.268-273
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• 2001

A fundamental study on the harvest-type ice storage system applied ice making method in-water and its temperature characteristics in ice storage system was performed experimentally of the charge and discharge of cold. This paper is concerned with the development of a new method for making and separating ice and saving floated ice by installing an evaporation plate at in-water within a storage tank. In a conventional harvest-type ice storage system, a tank saves ice by separating a formed ice from an installed evaporation plate, which is located above an ice storage tank as an ice storage system. A new harvest-type method shows very good heat transfer efficiency than a convectional method. It is because the evaporation panel is directly contacted with water in a storage tank. Also, at a conventional system a circulating pump, a circulating water distributor and a piping are installed, but these components are not necessary in a new method. In this study two kinds of ice storage systems are experimentally investigated to study the thermal characteristics of ice storage tanks.

• 설비공학논문집
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• 제11권3호
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• pp.301-312
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• 1999

Experiments were carried out to evaluate performance of the cold air distribution systems with an ice storage tank in test room. Cold air distribution systems provide primary air for comfort conditioning or process cooling at coil discharge temperatures$4^{\circ}C$ to$11^{\circ}C$. The application of a cold air distribution system allows for the downsizing of air distribution equipment and central plant equipment when ice storage tank is used. The benefit of a cold air distribution system include a decrease in the floor-to-floor height, increase floor space, reduced building capital costs, reduced energy use and demand. The use of cold air distribution can result in the most cost effective system and is currently being implemented world wise as the new standard in air conditioning systems. In this study, the cold air distribution system is compared with the general ice storage system. Under the same cooling load conditions, experimental results show that the supply air volume of cold air distribution system decrease 38%, and decrease 45% flow rate of brine for the general ice storage system.

• 설비공학논문집
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• 제14권1호
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• pp.31-37
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• 2002

This paper is concerned with the development of a new method for making and separating ice and saving floated ice by installing an evaporation plate at in-water within a storage tank. In a conventional harvest-type ice storage system, a tank saves ice by separating a formed ice from an installed evaporation plate, which is located above an ice storage tank as an ice storage system. A new harvest-type method shows very good heat transfer efficiency than a convectional method. It is because the evaporation panel is directly contacted with water in a storage tank. Also, at a conventional system a circulating pump, a circulating water distributor and a piping are installed, but these components are not necessary in a new method. In this study two kinds of ice storage systems are experimentally investigated to study the thermal characteristics of ice storage tanks. The results showed discharge of cold capacity of new type indicated the high values about 30~40% based on five time of drive, the temperature difference of inlet/outlet occurred the big range about $1.3^{\circ}C$. So, the new type which makes ice in water showed superiorly.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 추계학술대회논문집B
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• pp.210-215
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• 2000

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.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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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.

• 제어로봇시스템학회논문지
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• 제8권11호
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• pp.948-953
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• 2002

The electric power load during the peak time in summer is strongly affected by cooling load, which decreases the preparation ratio of electricity and brings about the failure in the supply of electricity in the electric power system. The ice-storage system and heat pump system are possible solutions to settle this problem. In this study. the method of estimating temperature and humidity to forecast the cooling load of ice-storage system is suggested, then the method of forecasting the cooling load using fuzzy logic is suggested by simulating that the cooling load is calculated using actual temperature and humidity. The forecast of the temperature, humidity and cooling load are simulated, and it is shown that the forecasted data approach to the actual data. Operating the ice-storage system by the forecast of cooling load with night electric power will improve the ice-storage system efficiency and reduce the peak electric power load during the summer season as a result.

• Journal of Advanced Marine Engineering and Technology
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• 제26권2호
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• pp.240-247
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• 2002

Recently, a thermal energy storage system has been developed actively fur the purpose of saving energy and reducing the peak electrical demand. Especially, ice slurry is a promising working fluid for low temperature energy storage systems. A flow of ice crystals has a large cooling capacity as a result of the involvement of latent heat. However, there are still problems related to the recrystallization of ice crystals for realizing long term storage and long distance transportation. To find improvements fur this, a method for the creation of ice crystals resistant to recrystallization has been proposed and researched by the use of an antifreeze protein (AFP) solution etc. In the present study, it has been investigated the growth of ice crystal in several kinds of water solution added non-ionic surfactant. The results shows that size of ice crystal was smaller with increasing in added surfactant. And ice crystal was not increased with added surfactant.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.286-291
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• 2001

This paper describes an optimal scheduling for ice slurry systems for energy cost saving. The optimization technique applied in the study is the dynamic programming method, for which the state variable is the storage in the ice storage tank and the control variable is the state of chiller's on-off switching. Though the costs during charge period is included in optimization by taking the average cost of ice per hour for slurry making, the time horizon for the simulation is limited building cooling period because accurate charge rate from the ice maker into the ice storage tank cannot be estimated during the charge period. In the operating simulation after optimizing procedure, energy consumption and operating cost for the optimal control are calculated and compared with them for a conventional control with one case of cooling load profile.

• 설비공학논문집
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• 제12권2호
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• pp.140-149
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• 2000

A comparative analysis was peformed on the operation cost at partial loads between ice storage systems with the two conventional control strategies, i.e., storage priority and chiller priority. The storage priority control is shown to be more economic for small cooling loads, while the chiller priority control is superior when the cooling load is as large as the design value. Based on this finding, a new control strategy is devised for an ice-storage system to minimize the operation cost at any cooling load. The new control strategy is found to be comparable to the chiller priority for large cooling loads, while it is more economic for small loads compared to the conventional control strategies. The practicality of the new control strategy is also confirmed through a performance test applying the new control strategy to an existing ice-storage system.