• 대한설비공학회지:설비저널
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• 제7권2호
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• pp.64-72
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• 1978

The determination of solar collector area requires a thermal simulation to evaluate the performance of a solar house. This study comprises a simulation of system performance including a solar house, flat-plate collectors, a water type storage tank and an auxiliary heater. Developing the steady state performance equations of each equipment, and using the actual monthly average weather data for several recent years, this study evaluates the hourly performance of a solar house model. As a result, it is shown that the desirable collector area in Seoul is 1.4-1.6 times larger than the heating area in the case of non-selective surface, 0.8-1.0 times in the case of selective surface.

• 대한설비공학회지:설비저널
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• 제9권2호
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• pp.93-103
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• 1980

A small domestic solar water heating system in thermosyphonic flow was tested in Seoul. The system consisted of four flat plate aluminium roll bond type collectors of total effective area $3.28m^2$ and a $280{\iota}$ storage tank. It was tilted $52^{\circ}$ relative to the horizon. And the collector plate, collector tube and storage tank were equiped with 14 thermocouples. As the results, the following facts were found; 1) To provide water at $55^{\circ}C$ for a family of four in Seoul, a collector area of $3-4m^2$ and a storage capacity of $180{\iota}- 200{\iota}$ are suggested. And this system can supply hot water at above $45^{\circ}C$ day about. 2) In the late afternoon hours, it might be advantageous to stop the flow in the system as heat losses to the environment increase unduly. 3) Without any hot water consumption throughout the day, water temperature distributions inside the storage tank was found almost linear. This indicates essentially no mixing inside the storage tank. 4) In case of a small domestic solar water heating system, it is better to employ a single transparent cover rather than double one.

• 대한기계학회논문집
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• 제9권5호
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• pp.579-589
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• 1985

본 논문의 모의 실험에 사용한 자연순환식 급탕 시스템과 지금까지 발표된 것 과의 차이점은 다음과 같다. 집열기의 집열성능 계산에 Close의 모델은 시스템의 평 균 온도를 이용하였으며, Mertol의 모델은 집열기의 성능을 일정하게 하여 자연순환식 급탕 시스템의 성능을 계산하였다. 그리고, Young의 모델은 집열기 입구 및 출구 유 체의 평균 온도로 집열기의 집열 성능을 계산하였다. Shitzer, Ong의 연구에서 밝혀 진 바와 같이 집열기 집열판의 온도와 유체 온도는 서로 다르므로, 본 논문에서는 이 것들에서 오는 오차를 줄이기 위해 집열기 순환 유체의 평균 온도와 집열판의 온도를 해석적으로 구하여 집열기의 성능과 순환 유체의 성질 계산에 이용하였다.

• 대한기계학회:학술대회논문집
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• 대한기계학회 2004년도 춘계학술대회
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• pp.1394-1399
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• 2004

Recently solar energy is representative in the technology development and spread of alternative energy. Specially in condition of solar collectors, they have had very various shape. This paper reports experimental study about the application of Oscillating Capillary Tube Heat Pipe to flat-plate solar collector. In conclusion, overall temperature distribution of OCHP was investigated by charging ratio and inclination angle. Respective charging ratio is 15%, 20%, 40% and respective inclination angle is horizontal, $30^{\circ}$, $45^{\circ}$, $60^{\circ}$, perpendicular. As a result of experiment, charging ratio 20% heat pipe has shown the most uniform temperature distribution and also performance of heat transfer has been the best.

• 에너지공학
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• 제22권3호
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• pp.302-306
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• 2013

A simple method for balancing flow rates in arrays of parallel connected flat plate solar collectors has been developed. The method is based on a computer program which solves for the flow rate through each of the collectors in a reverse return plumbed array. The analysis uses conventional "K-value" techniques and assumes the effects of density variations within the system to to be negligible. It has been found that by appropriately sizing the inlet and outlet manifolds, flow maldistribution can be nearly eliminated without resorting to expensive or complicated balancing techniques.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.559-562
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• 2006

A low-temperature solar thermal system assisting a biological nitrogen treatment reservoir was designed and field-tested. A large tank whose temperature was maintained at about $25{\sim}30^{\circ}C$ to enhance the performance of a biological nitrogen treatment process was heated by an array of flat plate solar collectors. Test results revealed that the overall collector efficiency was above 50% for the most cases tested. This high efficiency was possible owing to the relatively low collector temperature that can be traced back to the reservoir temperature. A substantial enhancement in nitrogen treatment was observed as a result of maintaining the reservoir temperature higher.

• Journal of Advanced Marine Engineering and Technology
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• 제37권4호
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• pp.316-323
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• 2013

평판형 태양열 집열기의 성능을 향상시키기 위하여 다양한 형태의 형상과 크기의 인공 거칠기가 가장 일반적이고 효과적으로 사용된다. 본 연구에서는 다양한 형상의 립을 삽입한 사각 채널에서의 열전달 특성 및 압력강하에 대하여 수치해석을 수행하였다. 사각 채널의 윗 평판에 일정한 열유속을 가하였다. 삽입된 립의 형상은 rib $90^{\circ}$, groove $90^{\circ}$, groove $60^{\circ}$, baffle $90^{\circ}$, baffle $60^{\circ}$, wave $90^{\circ}$, wave $60^{\circ}$ 모델이다. 작동유체는 공기이며 Reynolds 수는 3200~17800의 범위이다. 다양한 형태의 립 형상에 따른 시스템의 성능을 예측하기 위하여 Nusselt 수와 마찰인자를 고찰하였다. 모든 형태의 립에서 속도가 증가할수록 Nusselt 수와 압력강하는 증가하였다. 열전달 향상과 압력강하가 가장 높은 모델은 baffle $90^{\circ}$ 모델이지만, 열전달 특성과 압력강하를 고려하여 나타낸 성능계수에서는 groove $60^{\circ}$ 모델이 가장 크게 나왔다. 따라서 평판형 태양열 집열기에서는 열전달 향상과 압력강하를 항상 동시에 고려한 설계가 필요하다.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2006년도 춘계학술대회
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• pp.563-566
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• 2006

An investigation has been carried for the thermal characteristics of the seasonal storage installation in Cheju. It features the solar collector area of $340m^2$ and the storage capacity of $600m^3$. Four different types of solar collector systems are compared for their performance of collecting solar energy throughout the year. Of these, two are made of tubular shaped vacuum collectors and the others are flat plate collectors. Results indicate that each system could play an important role in exploiting solar energy depending on the temperature range in its operation. Especially, the vacuum collectors outperformed the others when the inlet temperatures of the collector loop were raised beyond $40m^2$. This became more conspicuous as the return temperatures from the storage tank rose reflecting the seasonal variation. Due to the large heat capacity of the storage tank, temperature changes were rather small compared to those in the collecting loop regardless of seasonal fluctuations.

• Applied Biological Chemistry
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• 제25권3호
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• pp.111-118
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• 1982

밀폐식(密閉式)물 교환태양(交換太陽) 열집열건조장치(熱集熱乾燥裝置)를 이용(利用)하여 홍삼(紅蔘)을 건조(乾燥)할때의 집열효율(集熱?率), 건조효율(乾燥?率). 건조특성(乾燥特性) 및 제품(製品)의 품질(品質)을 각각(各各) 조사(調査)하였다. 건조기간(乾燥期間)은 태양열집열장치(太陽熱集熱裝置)를 이용(利用)한 것이 관행법(慣行法)보다 3분(分)의 1정도(程度)를 더 단축(短縮)할 수 있었다. 건조기간중집열기(乾燥期間中集熱機)의 최대효율(最大?率)은 14.42% 최저효율(最低?率)은 4.73%였고 건조효율(乾燥?率)은 집열장치(集熱裝置)를 이용(利用)한 것이 28.34%, 대조구(對照區)가 13.45%로서 순수건조효율(純粹乾燥?率)은 14.89%이었다. 홍삼(紅蔘)의 건조율곡석(乾燥率曲線)은 감율건조기(減率乾燥期)만을 나타내었으며, 이때의 식(式)은 $Y=50.7023t^{-0.4138}$이었다. 건조홍삼(乾燥紅蔘)의 색도(色度)는 관행법(慣行法)과 비교(比較)하여 더 높았으며, diphenyl picryl hydrazyl 환원능(還元能)도 같은 경향(傾向)을 보였다.

• 한국태양에너지학회 논문집
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• 제31권3호
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• pp.57-66
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• 2011

A Photovoltaic/Thermal(PVT) solar system consists of PV module and thermal absorber plate which convert the absorbed solar radiation into electricity and heat. Meaningful researches and development (R&D) on the PVT technologies have been performed since the 1970s. This paper presents a review of the previous works covering the various types of PVT and their performance analysis in terms of electrical and thermal efficiency. This review compares electrical and thermal efficiency of the different types of PVT collectors and analyzes the parameters affecting PVT performance. Based on the literature review, box channel type PVT with unglazed, or flat plate PVT with glazed have the highest efficiency among them. From the literature review, R&D should be carried out aiming at improving their overall electrical and thermal efficiency, cutting down the cost, and making them more competitive in the energy consumption market.