• 한국지열·수열에너지학회논문집
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• 제13권4호
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• pp.8-13
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• 2017

The effects of operational conditions of cooling water system on energy consumption for central cooling system are researched by using TRNSYS program. Cooling tower water pump flow rate, cooling tower fan flow rate, and condenser water temperature with various dry-bulb and wet-bulb temperatures are varied and their effects on total and component power consumption are studied. If the fan maximum flow rates of cooling tower is decreased, cooling tower fan and total power consumptions are increased. If the cooling tower water pump maximum flow rates is decreased, chiller and total power consumptions are increased. If condenser water set-point temperature is increased, chiller power consumption is increased and cooling tower fan power consumption is decreased, respectively.

• 설비공학논문집
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• 제16권1호
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• pp.26-33
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• 2004

In general, an absorption chiller or heat pump is operated under the constant cooling water flow rate condition even though the system works with a partial load. The objective of this paper is to study the effect of the cooling water flow rates and the temperature of cooling water on the system performance to find the energy saving methode for the partial load operation of the double effect $H_2O$/LiBr absorption chiller. It is found that the performance of the system is sensitive to the temperature of cooling water than the cooling water flow rate, so the decrease of the performance due to reducing the cooling water flow rate can be overcome with the reduction of the cooling water temperature by 1$^{\circ}C$. The flow rate of the cooling water flow rate ranges from 50％ to 100％ of the flow rate at normal conditions with a partial load. It is also found that the operation cost of the cooling water pump and the cooling tower can be reduced by 23％.

• Journal of Electrical Engineering and Technology
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• 제9권3호
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• pp.882-887
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• 2014

In this paper, the water cooling method among the forced coolant cooling methods is considered to be applied to the 110kW-class IPMSM for railway vehicles. First, basic thermal property analysis of the IPMSM is conducted using the three-dimensional thermal equivalent network method. Then, based on the results of the basic thermal property analysis, some design requirements for the water cooling jacket are deduced and a basic design of the water cooling jacket is carried out. Finally, thermal equivalent circuit of the water cooling jacket is attached to the IPMSM's 3D thermal equivalent network and then, the basic thermal and effectiveness analysis are conducted for the case of applying the water cooling jacket to the IPMSM. In the future, the thermal variation trends inside the IPMSM by the application of the water cooling jacket is expected to be quickly and easily predicted even at the design step of the railway traction motor.

• 한국유체기계학회 논문집
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• 제17권6호
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• pp.84-88
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• 2014

A long term passive cooling system is considered as the most important safety feature for the nuclear design after the Fukushima Daiichi nuclear power plant accident in 2011. The conventional active pump driven safety systems are not available during a station Black Out (SBO) accident. The current design requirement on cooling time of the Passive Auxiliarly Feedwater System (PAFS) is about 8 hours only. To meet the 72 hours cooling time, the pool capacity of cooling water tank should be increased as much as 3~4 times larger than that of current water cooling tank. In order to extend the cooling time for 72 hours, a new passive air-water combined cooling system is proposed. This paper provides the feasibility of the combined passive air-water cooling system. The current pool capacity of water cooling system is preserved, and the cooling capability is extended by an additional air cooler.

• Corrosion Science and Technology
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• 제9권5호
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• pp.216-222
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• 2010

Most of the thirteen substations in operation in the metropolitan area were installed around the year 2000, and since water cooling methods are used to directly withdraw heat from transformer oils, a stable supply of electric power is required through optimal maintenance of facilities. The water cooling tower installed outdoors, which uses the water supply as sprinkler water, experiences the most problems. Since more than 90% of the cooling water is reused, the dissolved composition in the water becomes concentrated due to long operating hours, and impurities dissolve in the water due to air flowing in from the outside, forming hard scales on the outer surface of the cooling tube, and in extreme cases, reacting with the tube material composition, leading to corrosion. As a result, not only is cooling efficiency lowered, but in extreme cases the cooling tube must be replaced. In this study, the characteristics and composition of the scales formed on the cooling tube were analyzed and corrosion characteristics of material types were identified in order to find an efficient maintenance method for cooling tubes. In addition, the degree of dissolution of various chemicals were investigated during the removal of scales that have been formed.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2003년도 추계학술대회
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• pp.700-705
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• 2003

The general cooling tower is a device for making a cooling water in refrigerant condensers or industrial process heat exchangers. The present cooling tower have defects with noises, complicated structure and environmental problems. In this paper, we constituted a new water cooling system by using a evaporating latent heat in an enclosed tank, and this system is consisted of an enclosed vacuum tank and water driving ejector system. Several experimental cases were carried out for improvement methods of high vacuum pressure and water cooling characteristics. The ejector performance was tested in case of water temperature variations that flows in the ejector. Based on the vacuum pressure by water driving ejector, the water cooling characteristics were investigated for the vaporized air condensing effects.

• 한국해양공학회:학술대회논문집
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• 한국해양공학회 2006년 창립20주년기념 정기학술대회 및 국제워크샵
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• pp.209-212
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• 2006

Line heating with water cooling is generally adapted process in the shipyards for the forming hull surface. The purpose of this paper is to develop a model of thermal deformation in water cooling process after the line heating. In order to simulate the cooling process, heat transfer analysis was performed by assuming the effects of water cooling as a negative heat-source. Experiment for the line heating with water cooling was performed for 9 models of plates in order to verify the cooling model. By using the suggested model for the water cooling process, it could be observed that the present method predict the plate deformations in the line heating more accurately.

• 한국기계연구소 소보
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• 통권16호
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• pp.117-126
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• 1986

Trouble-free operation of cooling water systems is essential for efficient pro¬duction in most industrial facilities. Improper water treatments frequently cause such problems as corrosion, scaling, fouling and slime formation. Water quality, methods of cooling and materials of construction in the cooling circuit should be carefully studied before making selection of the water treatment programs. This paper reviewed cooling water problems encountered frequently in the open recirculating cooling systems and discussed the counter measures how to cope with them.

• 한국지열·수열에너지학회논문집
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• 제17권3호
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• pp.21-29
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• 2021

In this study, the current regulation of the water source energy, one of the renewable energy, was analyzed, and the improvement plan for the high efficient data center cooling system was suggested. In the improvement plan, the design and construction guidelines of the water source energy system permit to adopt the cooling and heating system with or without heat pump. In addition, it should also include the system operated in the cooling mode only all year-round. The domestic test standards to consider the water source operating conditions should be developed. Especially, it is highly recommended that the test standards to include the system with forced cooling and free cooling modes related with the enhanced data center cooling system adopting the water source energy.

• 오토저널
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• 제14권2호
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• pp.34-43
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• 1992

The purpose of this study is to consider the performance and exhaust characteristics in the practical engine according to the cooling water temperature change of engine and to set up the optimum cooling condition and to obtain the optimum operating condition of thermostat in the cooling system. In order to accomplish the purpose of this study, authors have used the following procedure. 1. This study is to investigate the influence of the cooling water temperature on the engine performance and the exhaust gas, authors regulated the cooling water temperature by using the special closing circuit and measured the concentration of exhaust gas by using the exhaust gas measuring system in the exhaust pipe. 2. This study carried out the experiment by regulating the opening degree of throttle valve and engine speed in the dynamometer and by changing the cooling water temperature, at the same time kept air-fuel ratio constant and made the spark ignition time MBT(Minimum spark advance for Best Torque) 3. This study measured the cooling water temperature by using the K-type thermocouple centring around the easy over-heated parts and by installing a special closing circuit. Therefore, in this study, authors intend to examine the influence of the cooling water temperature on the engine performance, exhaust gas and present the basic materials needed in the engine design including the optimum operating time control system for the cooling water temperature.