• 대한설비공학회지:설비저널
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• 제15권3호
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• pp.273-282
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• 1986

The purpose of this research was to study the characteristics of heat transfer in Heat Pipe which used the composition wick of screened groove - metallic mesh by ADI method and experimental results. As the results, the more than number of metallic mesh screen layers in a heat pipe increased, the fewer the effect of heat recovery decreased. In case of 1 - layer metallic mesh screen wick, the response of the effect in heat recovery was more rapidly showed than in case of other layers and in spite of high load, the evaporation section of Heat pipe with 1 - layer metallic mesh screen wick showed the stable response and did not show excessive super heat. There was a interrelation between thermal resistance and the variable layers, between thermal resistance and the variable gaps of metallic meshes, the heat transfer characteristics of Heat pipe were depended on the thermal resistance of composition wick.

• 설비공학논문집
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• 제12권10호
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• pp.894-900
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• 2000

The experimental study for performance improvement of aluminum/freon22 grooved heat pipe was carried out. Arterial wick was used for performance improvement of heat pipe. The experimental result was compared with screen covered grooved wick heat pipe. And also, performance test of grooved wick thermosyphon inserted straight wire in the center of grooved pipe was carried out. This result was compared with the performance test result of grooved wick thermosyphon. The operation limit of artery inserted grooved heat pipe was slightly extended, but thermal resistance of this heat pipe was twice as large as that of screen covered grooved heat pipe. In case of thermosyphon, the operation limit of grooved thermosyphon inserted straight wire in the center of grooved pipe was slightly extended, but thermal resistance was increased, comparing with that of the grooved thermosyphon.

• 설비공학논문집
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• 제13권6호
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• pp.474-481
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• 2001

Aluminum/Freon22 grooved hat pipes which have 26 axial grooves in a cross-section were manufactured and tested. The performance test was conducted by varying filling ratio and tilt angle. Operation limit, thermal resistance, overall heat transfer coefficient were investigated. The experimental result was compared with previous study which conducted in the case of a heat pipe with combined wick. The experimental result shows that thermal resistance of this heat pipe is twice smaller than that of the heat pipe with combined wick and operation limit is increased about 75%, comparing with that of heat pipe with combined wick.

• 설비공학논문집
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• 제11권2호
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• pp.236-243
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• 1999

Aluminum/Freon-22 heat pipes were manufactured and tested which have a special wick geometry combining axial groove and screen mesh. There were 14 axial grooves in a cross-section and these were covered by two layers of 350 mesh screens to enhance the thermal performance. The performance test was conducted by varying the thermal load and tilt angle. Furthermore, the operation limits and overall heat transfer coefficient were investigated. The experimental results will be useful in a variety of applications, especially in design and manufacturing of a high-efficiency heat exchanger and energy recovery systems.

• International Journal of Air-Conditioning and Refrigeration
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• 제12권2호
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• pp.79-86
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• 2004

An analytical and experimental study has been conducted to determine the optimal charging mass of working fluid for the maximum heat transport capacity of heat pipe with axially grooved wick. When the heat pipe is operated in a steady state, the liquid-vapor meniscus recession of working fluid to the bottom of groove is occurred in the evaporator region. In this work, the optimal charging mass of working fluid was obtained by considering the meniscus recession from the axial variation of capillary pressure, the radius of curvature and wetting angle of meniscus of liquid-vapor interface. Experimental results were also obtained by varying the charging mass of working fluid within a heat pipe, and presented for the trend of maximum heat transport capacity corresponding to the operating temperature and the elevation of heat pipe. Finally, the analytical results of the optimal charging mass of working fluid were compared with those from the experiment, both of which were in good agreement with each other.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 동계학술발표대회 논문집
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• pp.317-322
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• 2005

This study is aimed to analyze the effects of heat pipe shape on the heat transfer in solar collector with a axial grooved heat pipe. In the design of a heat pipe. two of the most important criteria to be met are the operating temperature range and the maximum heat transport capacity, When the operating temperature range is known and the working fluid has been selected, the maximum heat transport capacity depends strongly on capillary pressure and liquid flow. The heat transport capacity of the heat pipe will depend on the geometry of the heat pipe, the wick structure. the vapor channel shape. groove number. cooling temperature. condenser length and pipe diameter. So various shapes are used for mathematical models of two-phase flow in grooved heat pipe. From the results. the adequate groove shape and scale are presented by considering the heat transport and capillary limitation.

• 대한기계학회논문집B
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• 제29권6호
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• pp.747-754
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• 2005

Because the liquid-vapor interfacial shear stress affects seriously the liquid flow and the maximum heat transport rate of the grooved wick heat pipe, an accurate modeling for the pressure drop characteristics of the liquid flow is required. A novel method for calculating the liquid pressure drop and the velocity profile of an open channel flow in a microchannel with an arbitrary cross-section is suggested and validated by experiments. An experimental apparatus for the Poiseuille number of the liquid flow in open rectangular microchannels with the hydraulic diameters of 0.40mm, 0.43mm, 0.48mm is used in order to reproduce real situations in the grooved wick heat pipe. Analytic results from the suggested method are compared with the experimental data and they are in a close agreement with each other.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2012년도 춘계학술대회 논문집
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• pp.691-692
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• 2012

• 태양에너지
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• 제9권2호
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• pp.31-41
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• 1989

The purpose of this research is to study the utility of prediction program like a F.E.M. analysis for energy recovery of heat exchanger with heat pipe which uses arbitrary groove wick. The program is based on the utility by the experimental and applytical method of the single heat pipe. It is also expanded and applied in the prediction program of the heat exchanger. The results are as follows; 1) The effective thermal conductivity of the groove wick with arbitrary shape is counted by the thermal resistance change. 2) The more the number of rows, the more the effect energy recovery changing by the number of rows, the bigger the free velocity, the smaller the effect of energy recovery. 3) The effect of energy recovery increases according to the value of the rate of mass flow (Me/Mc) and also number of rows. 4) The comparison between calculated and data shows good agreement within 2.5% error, therefore the F.E.M. analysis of the study is useful to predict the performance of heat pipe-heat exchanger.

• 대한기계학회논문집B
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• 제40권11호
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• pp.755-759
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• 2016

전자 통신 분야에서 히트파이프를 활용한 방열기술은 점차 늘어나고 있다. 특히 전자 패키지 응용에서는 원형 단면 히트파이프에 비해 평판 형상의 얇은 히트파이프가 보다 더 적용하기에 용이하다. 압출 공정에 기반한 평판 히트파이프는 내벽에 사각 단면 그루브들로 이루어진 단순한 모세관 윅 구조를 갖는다. 그루브 윅이 내벽에 다수 개 설치가 된다고 하더라도 상대적으로 높은 모세관력을 달성하기는 어렵다. 본 연구에서는 그루브 윅의 모세관력 향상을 위해 와이어 다발을 적용한 평판 히트파이프의 제작 및 성능평가 실험을 수행하였다. 실험을 통해 와이어 다발을 윅으로 갖는 평판 히트파이프의 열저항 및 열전달률이 그루브 윅 평판 히트파이프에 비해 각각 3.4배와 3.8배 가량 우수한 것으로 나타났다. 본 연구를 통해 와이어 다발을 통한 모세관력 향상 효과를 실험적으로 확인하였으며, 향후 상용화를 위한 연구를 진행할 계획이다.