• 국제초고층학회논문집
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• 제12권4호
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• pp.335-341
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• 2023

This study proposes a novel rotary direct evaporative cooler and investigates the potential of a moisture-wicking fabric as a cooling pad for the proposed evaporative cooler. The rotary direct evaporative cooler rotates the cooling pad to reduce the water and energy consumption of the pump compared to those of existing direct evaporative coolers. A moisture-wicking fabric is considered as the material of the cooling pad, because of its high moisture-wicking property, enhancing water evaporation. Experiments are performed under various inlet air conditions while measuring the air temperature, relative humidity, air velocity, and differential pressure. The evaporative cooling efficiency and impacts of the inlet air temperature and air velocity on the cooling performance are also evaluated. The results demonstrate the potential of the moisture-wicking fabric as cooling pad of direct evaporative cooler.

• 한국철도학회:학술대회논문집
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• 한국철도학회 2011년도 춘계학술대회 논문집
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• pp.43-48
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• 2011

Cooling system's operation ratio shall be controlled automatically by the internal external temperature sensors in rolling stock. The Cooling System shall be the automatic operation ratio control system which automatically controlling the rotation speed of condenser, evaporator etc. using temperature detection from outside and inside of cabin. This paper will examine the cooling system that can be provide comfortable cooling service for passenger in summer.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.77-82
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• 2000

Parametric study fur the cooling characteristic investigation of a notebook PC mounted with heat spreader has been numerically performed. Two oases of air-blowing and air-exhaust at inlet were tested. The cooling effect on Parameters such an, velocities of air-blowing and air-exhaust, materials of heat spreader, and CPU powers were simulated for two cases. Cooling performance in the case of air-blowing was better than the case of air-exhaust.

• 대한기계학회논문집A
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• 제34권10호
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• pp.1487-1492
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• 2010

본 논문의 목적은 3 차원 사출성형해석을 통한 냉장고 플라스틱 서랍 제작용 사출성형 금형의 형상적응형 냉각수로 설계이다. 바람직한 형상적응형 냉각수로의 설계를 얻기 위하여 형상적응형 냉각수로의 직경과 위치가 사출성형 특성과 제품의 품질에 미치는 영향을 정량적으로 고찰하였다. 해석결과로부터 제품의 균일 냉각과 변형 최소화가 가능한 최적의 형상적응형 냉각수로의 설계를 도출할 수 있었다. 본 연구에서 제안된 사출성형 금형과 기존의 직선형 냉각수로의 사출성형 금형을 냉각/제품 제작 시간 및 제품 품질 측면에서 비교한 결과, 형상적응형 냉각수로를 가진 사출성형 금형이 제품의 생산성과 품질을 동시에 향상시킬 수 있음을 알 수 있었다.

• 한국기계가공학회지
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• 제13권2호
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• pp.124-130
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• 2014

In a mass manufacturing system of optical fibers, the sufficient cooling of glass fibers freshly drawn from a draw furnace is essential, asinadequately cooled glass fibers can lead to poor resin coating on the fiber surface and possibly fiber breakage during the process. In order to improve fiber cooling at a high drawing speed, it is common to use a helium injection into a glass fiber cooling unit in spite of the high cost of the helium supply. The present numerical analysis carried out three-dimensional thermo-fluid computations of the cooling gas flow and heat transfer on moving glass fiber to determine the cooling performance of glass fiber cooling depending on the method of helium injection. The results showed that afront injection of helium is most effective compared to a uniform or rear injection for reducing air entrainment into the unit and thus cooling the glass fibers at a high fiber drawing speed. However, above a certain amount of injected helium, there was no more increase of the cooling effect regardless of the helium injection method.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2001년도 춘계학술대회논문집D
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• pp.127-132
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• 2001

An experimental study on penetration integrity of the reactor vessel has been performed under external vessel cooling during a core melt accident. In this study a series of experiments are performed for the verification of the effects of coolant in the annulus between the ICI(In-Core Instrumentation) nozzle and the thimble tube and also the effects of external vessel cooling on the integrity of the penetration using the test section including only one penetration and $Al_{2}O_{3}$ melt as a corium simulant. The experimental results have shown that penetration is more damaged in the case of no external vessel cooling compared with the case of external vessel cooling. It is preliminarily concluded that the external vessel cooling is very effective measure for the improvement of the penetration integrity. Also it is confirmed from the experimental results that the coolant in the annulus reduces the melt penetration distance through the annulus and enhance the integrity of the reactor vessel penetration in the end.

• 한국자동차공학회논문집
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• 제21권6호
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• pp.1-7
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• 2013

This paper focuses on cooling fan control by using a magnetic clutch type for the improvement of fuel economy on a heavy city bus. In general, Heavy duty vehicles use viscous clutch type cooling fan which has some disadvantages, such as slow response, wide temperature variation of engine coolant water. But a magnetic clutch type cooling fan can be controlled electronically so the engine coolant temperature can be precisely controllable and this effects could be used to reduce fuel consumption. A control system for applying the magnetic clutch type cooling fan was developed in this study and applied to the real field test and chassis dynamometer test. The result showed well controlled coolant temperature and enhancement of fuel economy.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2009년도 하계학술발표대회 논문집
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• pp.1288-1293
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• 2009

The TES (Thermal Energy Storage) cooling system utilizing cheaper off-peak electricity has been applied just for building air-conditioning currently and causes limitation of usage rate and inefficiency of national resources utilization. In this regard, more says the necessity to apply TES system in industrial cooling system which is longer using period and wider usage. In this study, we will approve the technical and economical improvement in efficiency of industrial cooling system applied TES system by utilizing cheaper off-peak electricity and it will attribute the promotion of TES system and stabilization of supply and demand of electric power by proving the necessity to develop more efficient industrial cooling system by combining TES system.

• 대한기계학회논문집B
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• 제28권7호
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• pp.780-788
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• 2004

This paper reports the fluid flow and heat transfer around a module cooled by forced air flow generated by a piezoelectric(PZT) cooling fan. The fluids are locally accelerated by a flexible PZT fan which deflects inside a fluid transport system of comparatively simple structure mounted on a PCB in a parallel-plate channel(450${\times}$80${\times}$700㎣). Input voltages of 20-100V and a resonance frequency of 23㎐ were used to vibrate the cooling fan. Input power to the module was 4W. The fluid flow around the module was visualized by using PIV system. The temperature distributions around a heated module were visualized by using liquid crystal film(LCF). The cooling effect using a PZT fan was independent of the vent area ratios at the channel inlet and was similar to the forced convection cooling. We found that the flow type was Y-shape and the cooling effect was increased by the wake generated by a piezoelectric cooling fan.

• 한국주조공학회지
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• 제29권5호
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• pp.238-243
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• 2009

This study has been carried out to investigate the cooling ability improvement of diecasting mold by decompression cooling system. The decompression cooling system was applied to the new/used oil pump cover molds. The temperature of the surface mold applied the decompression cooling system fell to 15 degrees, especially in case of the used mold. The defect ratio of the oil pump cover manufactured by decompression cooling system has decreased from 2.8 percent to 0.2 percent. According to the results of the cooling ability improvement of diecasting mold by decompression cooling system, the decompression degree and supply pressure were set up the control item to apply the decompression cooling system to the diecasting mold in the industry field.