• 설비공학논문집
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• 제10권1호
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• pp.44-55
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• 1998

The evaluation of aluminum flat tube and louver fin heat exchangers for a condenser in residential air-conditioning applications has been conducted. A series of tests for two-different brazed aluminum heat exchangers was performed and the results were compared with conventional fin and tube heat exchangers for residential air-conditioning system. Refrigerant charge amount for a window-system air-conditioner with the brazed aluminum condenser is decreased by 35% and the volume and material of heat exchanger can be reduced by 50% compared to the conventional fin and tube heat exchangers.

• 한국산학기술학회논문지
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• 제10권2호
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• pp.222-229
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• 2009

본 논문에서는 루버형 핀 형상을 가진 핀-튜브 열교환기와 알루미늄 평행류 열교환기의 에어컨 응축기 조건에서의 열전달 성능과 공기측 압력강하 특성을 비교하였다. 모든 실험은 ASHRAE 표준에 근거해 제작된 공기엔탈피형 칼로리미터를 사용하여 수행하였다. 관외 측 공기 속도는 0.7-1.6 m/s까지 0.3 m/s 간격으로 변화시켰으며 건구온도는 $20^{\circ}C$, 상대습도는 60%로 유지하였다. 관내 측 물의 입구온도는 $70^{\circ}C$, 유량은 10 LPM로 고정하였다. 알루미늄 열교환기의 열전달 성능은 루버 핀-튜브 열교환기보다 단위체적당, 단위질량당, 단위열전달면적당 약 17-163%정도 높게 나타나는 연구결과를 보였으며 반면에 공기측 압력강하는 핀-튜브 열교환기에 비해 약 19-81% 정도 낮게 나타났다.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2008년도 동계학술발표대회 논문집
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• pp.525-530
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• 2008

In the present study, the cooling performances of the air-conditioner applied the fin-tube and aluminum PF heat exchangers have been experimentally investigated by using the calorimeter. The experiment is carried out in the conditions of the standard temperature and the low temperature. Fin type of PF heat exchanger is a triangler and squarer form. PF heat exchanger has smaller refrigerant weight and larger capacity and COP han the fin-tube heat exchanger. The performance of PF-2 heat exchanger with the squarer in is more excellent than that of PF-1 heat exchanger with the triangler fin. The high pressure of PF heat exchanger decreases about 7%, compared to the fin-tube heat exchanger. Also, CSPF of the fin-tube and PF heat exchanger is evaluated.

• 농업생명과학연구
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• 제44권4호
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• pp.29-43
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• 2010

The numerical analysis by using CFX 11.0 commercial code was done for proper design of the heat exchanger. The present experimental studies were also conducted to investigate the effects of circulating solid particles on the characteristics of fluid flow, heat transfer and cleaning effect in the fluidized bed vertical shell and tube type heat exchanger with counterflow, at which a variety of solid particles such as glass ($3mm{\Phi}$), aluminum ($2{\sim}3mm{\Phi}$), steel ($2{\sim}2.5mm{\Phi}$), copper ($2.5mm{\Phi}$) and sand ($2{\sim}4mm{\Phi}$) were used in the fluidized bed with a smooth tube. Seven different solid particles have the same volume, and the effects of various parameters such as water flow rates, particle diameter, materials and geometry were investigated. The present experimental and numerical results showed that the flow velocity range for collision of particles to the tube wall was higher with heavier density solid particles, and the increase in heat transfer was in the order of sand, copper, steel, aluminum, and glass. This behavior might be attributed to the parameters such as surface roughness or particle heat capacity.

• 설비공학논문집
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• 제17권9호
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• pp.839-848
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• 2005

Plastic plate heat exchangers have many advantages over the conventional heat exchangers such as aluminum plate heat exchangers, rotary wheel heat exchangers and heat pipe heat exchangers which have been used for ventilation heat recovery in the air-conditioning systems. In the present study, pressure drop and heat transfer characteristics of plastic plate heat exchangers are investigated for various design parameters and operating conditions which affect the performance of the plastic plate heat exchangers. In flat plate type heat exchanger, material thickness and channel height of heat exchanger are considered, and corrugate size and heat transfer area are considered in case of corrugate type heat exchanger. Pressure drop and effectiveness of the corrugate type heat exchanger increase as the corrugate size decreases.

• 한국지열·수열에너지학회논문집
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• 제14권1호
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• pp.22-29
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• 2018

The purpose of this study is to investigate the preliminary thermal performance of a plastic coated aluminum material(PCAM) plate heat exchanger. Plastic coating which has high corrosion resistivity and thermal conductivity can overcome corrosive weakness of aluminum material. The heat exchangers are modeled for STS316, Titanium and PCAM materials, and analyzed numerically using HTRI and ANSYS Fluent CFD softwares. The results show that PCAM heat exchanger is superior in heat transfer performance compared to existing materials. For chevron angle of $60^{\circ}$, thermal performances of Titanium and PCAM are higher by 12.2% and 48.9% when compared to STS316, respectively.

• Journal of Mechanical Science and Technology
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• 제16권9호
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• pp.1175-1182
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• 2002

The commercial viability of heat exchanger is mainly dependent on its long-term fouling characteristic because the fouling increases the pressure loss and degrades the thermal performance of a heat exchanger. An experimental study was performed to investigate the characteristics of fluid flow and heat transfer in a fluidized bed heat exchanger with circulating various solid particles. The present work showed that the higher densities of particles had higher drag force coefficients, and the increases in heat transfer were in the order of sand, copper, steel, aluminum, and glass below Reynolds number of 5,000.

• 한국산학기술학회논문지
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• 제14권10호
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• pp.4658-4664
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• 2013

본 논문은 심층수 이용 열교환기 개발을 위해 열교환기의 구성 재질로서 티타늄, 알루미늄, 스테인리스, 철, 구리와 알루미늄의 전착코팅 관 등을 이용한 이중관 열교환 실험 장치를 구성하여 열교환 성능을 실험하였다. 기존 심층수 이용 열교환기는 대부분 티타늄 금속으로 이루어져 있다. 티타늄의 재질은 해양 심층수에 적합하나 고가의 금속이다. 티타늄 금속을 대체할 금속으로 알루미늄, 스테인리스, 철, 구리와 알루미늄 전착코팅 관 등을 고려하여 시험하였다. 또한 EES 프로그램을 사용하여 각 관들의 열전달률을 해석하고 이중관 열교환 실험결과와 비교 분석하였다. 열교환시의 성능에 대한 해석값과 실험값을 비교해 보았을 때 10% 내외의 오차범위 내에서 잘 일치하였다. 또한 티타늄 대비 구리관이 가장 좋은 결과치를 보였고 알루미늄 전착코팅 관은 다소 낮은 열전달 수치를 보여 주었으나, 전착처리된 코팅관의 내부식성이 우수한 것을 고려한다면 티타늄 대체가능성이 충분하다고 사료된다.

• 한국산학기술학회논문지
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• 제14권11호
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• pp.5377-5384
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• 2013

본 논문은 심층수용 열교환기 재질로 티타늄, 알루미늄, 스테인리스, 구리와 알루미늄을 코팅하여 재질의 특성 및 부식이 미치는 영향을 조사하기 위하여 이중관 열교환 실험장치를 활용하였다. 열교환기 재질은 티타늄, 스테인레스, 구리, 알루미늄, 카본 코팅된 알루미늄 등 6종이 비부식관과 부식관에 대하여 해석과 실험이 수행되었다. 해석은 EES 프로그램을 사용하였다. 부식의 영향을 살펴보기 위하여 부식 제조장치를 제작하고, 3.5%의 염수를 $70^{\circ}C$의 온도로 약 6주간 담가서 가속부식을 실시하였다. 부식된 관으로 이중관 열교환기의 성능실험을 실시하여 비부식관과 비교하였다. 실험결과로부터 티타늄을 대체용으로 알루미늄 코팅관(카본 블랙 $150{\mu}m$)의 가능성을 확인하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2000년도 춘계학술대회논문집B
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• pp.7-12
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• 2000

The purpose of this study is to develop heat transfer analysis program of heat pipe elements and design a revolving heat pipe exchanger by the performance experiment of hot air production by means of middle-temperature waste heat. Experimental variables are the revolution per minute, normal velocity of inlet air and the temperature of waste heat. The revolving heat exchanger has designed as $2^{\circ}$ in inclination angle of heat pipe bundle and as 20% in working fluid quantity and as water in working fluid. Experimental value of the total heat transfer coefficient was $20w/m^2-^{\circ}C$