• Title/Summary/Keyword: Cooling

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DEVELOPMENT OF NIGHT COOLING SYSTEM FOR GREENHOUSE USING COOL AIR AND WATER FROM AN ABANDONED COAL MINE

  • Whoa S. Kang;Wie S. Kang;Lee, Gwi H.
    • Proceedings of the Korean Society for Agricultural Machinery Conference
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    • 1996.06c
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    • pp.1136-1145
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    • 1996
  • This study was to develop the most effective cooling system which is needed to cool greenhouse during summer night to get early blooming of strawberries. Various cooling systems were designed and constructed to utilize the cool air and water from tan abandoned coal mine. Cooling systems built for this study were an evaporative cooling system with pad, cooling system using a small or large radiator , and duct cooling system using cool are drawn from coal mine. These systems were individual tested to investigate their effects on cooling greenhouse during summer night. Also, a combined cooling system was tested with operating an evaporative cooling system, small radiator, and duct cooling system simultaneously. The results in this study showed that individual cooling systems such as evaporative cooling system, small radiator, and cooling duct had about the same effect on cooling greenhouse. The combined system had little better cooling effect than that of individual cooling syst m except the large radiator . The most effective system for cooling of greenhouse was obtained with using a large a large radiator as the heat exchanger. With operating a large radiator, temperature inside the greenhouse was dropped to about 15-16$^{\circ}C$ while outside temperature was 23-24$^{\circ}C$ during summer night.

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Development for Inserted Type Coling System in Computer (컴퓨터 내장형 냉각시스템 개발)

  • Lee, Hyeon-Yong;Im, Seon-Jong
    • Proceedings of the Safety Management and Science Conference
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    • 2009.11a
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    • pp.399-404
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    • 2009
  • The research for computer cooling system has been researched briskly at home and abroad. Most of computer cooling systems are the air cooling method using cooling fan. The air cooling system are most widely used for low cost and easy installation but have limits in cooling. The water cooling system are good for cooling efficiency but bad for installation. This paper presents the developing for cooling system to be inserted in computer using thermoelectric module.

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Evaluation for the Cooling Capability of Secondary Cooling Tower in HANARO (하나로 2차 냉각탑의 냉각능력 평가)

  • Park, Yong-Chul;Wu, Jong-Sup;Cho, Yeong-Gurb;Ryu, Jeong-Soo
    • 유체기계공업학회:학술대회논문집
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    • 2000.12a
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    • pp.345-350
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    • 2000
  • The heat produced by the fission in the fuel of HANARO, 30 MW research reactor, is transferred from the primary cooling water to the secondary cooling water through heat exchangers, and the heat absorbed by the secondary cooling water is released into the atmosphere by the 33 MW cooling tower which is a mechanical induced draft and counter flow type. If the outlet temperature of cooling tower exceeds 33 of due to the loss of the cooling tower performance under reactor operation above $50\%$ of the full power, the reactor power should be reduced to half of the full power for safe operation. Therefore, the cooling capability of cooling tower should be maintained for the reactor to be normally operated. To predict the capability of cooling tower for full power reactor operation of 30 MW, the performance test of cooling tower was done at the reactor present power of 24 MW and the capability was respectively evaluated by characteristics and performance curves methods in accordance with the Code of Cooling Tower Institute of U.S.A. to confirm the reliability of evaluation. As a result, it was confirmed, through the results of each evaluation, that the cooling capability of cooling tower meets the design required heat load. Also, the equations of the performance and the characteristics curves of the cooling tower, based on the collected data during this performance test, was obtained for developing the calculation program to predict the cooling capability during reactor operation.

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A Study on the System Integration and Control Method of Radiant floor Cooling in Apartment Buildings (공동주택에서 바닥복사냉방의 시스템 구성과 제어 방안에 관한 연구)

  • 조영흠;석호태;김광우;여명석
    • Journal of the Korean housing association
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    • v.15 no.2
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    • pp.107-115
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    • 2004
  • The objective of this study is to show the system Integrations and control method for operation of the Radiant Floor Cooling. The systems for radiant floor cooling system consist of only using the radiant floor cooling and the radiant floor cooling integrated with a dehumidification system. And the study is suggested control method with composed radiant floor cooling system through simulations. Radiant floor cooling systems compose of four main parts: an existing radiant heating panel, manifold, cooling source and controller, and sensors. If dehumidifying or supplementary cooling is needed, additional equipments such as PAC and AHU are needed. Simulation results show that control method only using radiant floor cooling system can prevent condensation and set room air temperature with the exception of hot and humid periods and control method using the radiant floor cooling integrated with a dehumidification system is comfort thermal environments and can reduce the cooling load quickly, moreover, show comfort control method to meet various cooling operation situations.

NUMERICAL STUDY ON FILM-COOLING EFFECTIVENESS FOR VARIOUS FILM-COOLING HOLE SCHEMES (다양한 막냉각 홀 형상에 대한 막냉각 효율의 수치해석)

  • Kim, S.M.;Lee, K.D.;Kim, K.Y.
    • Journal of computational fluids engineering
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    • v.16 no.4
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    • pp.92-99
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    • 2011
  • In order to protect the turbine blade from working fluid of high temperature, many cooling techniques such as internal convection cooling, film cooling, impinging jet cooling and thermal barrier coating have been developed. With all other things, film-cooling has been widely used as the important alternative. In the present work, numerical analysis has been performed to investigate and to compare the film-cooling performance of various film-cooling hole schemes such as cylindrical, crescent, louver, and dumbbell holes. To analyze the turbulent flow and the film-cooling mechanism, three-dimensional Reynolds-averaged Navier-Stokes analysis has been performed with shear stress transport turbulence model. The validation of numerical results has been assessed in comparison with experimental data. The characteristics of fluid flow and the film-cooling performance for each shaped hole have been investigated and evaluated in terms of centerline, laterally averaged and spatially averaged film-cooling effectivenesses. Among the film cooling holes, the dumbbell shaped hole shows better film-cooling effectiveness than the other shaped holes. And the louver and cylindrical shaped hole show the worst film cooling performance, and concentrated flows on near the centerline only.

A Study on the Operation Strategy of Radiant Floor Cooling in Apartment Buildings (공동주택에서 바닥복사냉방의 적정 운영방안에 관한 연구)

  • 조영흠;석호태;여명석;김광우
    • Korean Journal of Air-Conditioning and Refrigeration Engineering
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    • v.16 no.6
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    • pp.574-583
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    • 2004
  • In this study, the operation strategy of the radiant floor cooling is evaluated in terms of indoor environmental conditions and energy consumption through simulations using the TRNSYS comparing the existing cooling operation. The operation strategy during continuously operated for cooling is proposed that a representative room had additional equipments and other rooms were operated with only a radiant floor cooling system and that system and control method for cooling are varied with period while intermittently operated for cooling. Specifically, when there are no people in the room, rooms were operated by only radiant floor cooling system using cooling storage and when people are occupied, rooms were operated by dehumidification and supplementary cooling device with radiant floor cooling system. The results of this study show that proposed operation strategy can stably maintain the set room air temperature and can reduce the energy consumption compared to the existing cooling method during continuously operated for cooling. While intermittently operated for cooling, the difference of set room air temperature by proposed operation strategy does not happen, satisfying comfort standards and the radiant floor cooling can expect to supply stable electric power because of decreasing demand for peak electric power of energy consumption.

Investigation of Cooling Performance of the Driving Motor Utilizing Heat Pipe (히트파이프를 부착한 구동모터의 냉각성능에 관한 연구)

  • Lee, Dong-Ryul
    • Journal of Power System Engineering
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    • v.10 no.4
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    • pp.11-16
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    • 2006
  • This research is to verify the cooling effect of the acting surface on the rotary motor using heat pipe and conventional cooling fan. In order to show the cooling performance of the rotary motor and heat pipe with the fin-typed heat sink, the surface temperature of the motor and condenser was measured in real time. The experiments were also conducted as for not only cooling device installed with heat pipe only, but with heat pipe and conventional cooling fan simultaneously. The present experiment reveals that the cooling combination of the heat pipe and cooling fan is far superior to the conventional cooling device for the driving motor such as the fin-typed heat sink. When the driving voltage of 20V and 14V were supplied to the driving motor, the cooling performance of the rotary motor with heat pipe was 170% and 500%, respectively better than that without heat pipe on steady state condition.

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Study of Efficient Cooling Part for Cooling Clothes Development (냉각복 개발을 위한 효율적 냉각부위 규명에 관한 연구)

  • 최정화;황경숙
    • Journal of the Korean Society of Clothing and Textiles
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    • v.26 no.6
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    • pp.771-778
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    • 2002
  • Cooling clothes especially cooling vest are being considered for as an efficient way to reduce heat strain under hot environment. But wearing ice gel or ice-based cooling vest caused discomfort to subjects due to the weight of vest. Therefore, this study was executed to find efficient cooling parts and to reduce vest weight by cooling only these parts. Two male subjects were exposed to heat(40$^{\circ}C$, 30%RH) with A type(breast+back+abdomen+waist), B type(breast+back+waist), C type(breast+back+abdomen) and D type(breast+back) cooling vest that distinguished with cooling part. The results were as follows; When subjects were C type and D type vest, sweat volume was less and skin temperature was low. Heart rate and rectal temperature were low in B type and D type. These results suggest that excessive cooling of breast and abdomen may exert a bad influence to health and cooling of back is desirable.

The Effects of Operational Conditions of Cooling Water System on Energy Consumption for Central Cooling System (냉각수 계통의 운전변수가 중앙냉방시스템의 에너지소비량에 미치는 영향)

  • Ahn, Byung-Cheon
    • Journal of the Korean Society for Geothermal and Hydrothermal Energy
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    • v.13 no.4
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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.

Experimental Studies on the Stack Cooling Performance Using a $CO_2$ Air Conditioning System in Fuel Cell Vehicles (이산화탄소 에어컨 시스템을 이용한 연료전지 자동차의 스택 냉각성능에 대한 실험적 연구)

  • Kim, Sung-Chul;Kim, Min-Soo;Won, Jong-Phil
    • Transactions of the Korean Society of Automotive Engineers
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    • v.16 no.3
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    • pp.87-93
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    • 2008
  • The $CO_2$ air conditioning system installed in fuel cell vehicles could be used either for stack cooling or for cabin cooling, and thus was used for the stack cooling when additional stack heat release was required over a fixed radiator capacity for high power generation. This study investigated the performance of the stack cooling system using $CO_2$ air conditioner at various operating conditions. Also, the heat releasing effectiveness and mutual interference were analyzed for the stack cooling system using an air conditioner and compared with the conventional radiator cooling system with/without cabin cooling. The heat release of the stack cooling system with the aid of $CO_2$ air conditioner increased up to 36% more than that of the conventional radiator cooling system with cabin cooling. Furthermore, the heat release of the stack cooling system using $CO_2$ air conditioner increased more by 7% than that of the conventional radiator cooling system without cabin cooling.