• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2006년도 하계학술발표대회 논문집
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• pp.965-969
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• 2006

This study investigated heat transfer characteristics between absorber and heat pipe used to extract heat from concentric evacuated tubular collectors. In order to experiment, T-type thermocouples are attached to a evaporator of heat pipe and absorber of inner tube. A wall temperature distribution of absorber and heat pipe were carried out by experimental method under actual various ir-radiance and outdoor conditions. As a result, As to increase an irradiance, a wall temperature of absorber and heat pipe is gradually increased. The heat pipe was required about 20min to obtain steady state operation after start up and operates stable during various irradiance conditions. And the collector efficiency was about $50{\sim}70%$ when a mass flow rate is about $1.3{\ell}/min$.

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2005년도 하계학술발표대회
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• pp.129-129
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• 2005

• 대한설비공학회:학술대회논문집
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• 대한설비공학회 2004년도 하계학술발표 논문집
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• pp.152-152
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• 2004

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 추계학술발표대회 논문집
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• pp.214-219
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• 2008

This study is describes thermal performance of solar cooling and hot water for demonstration system with ETSC(Evacuated tubular solar collector) installed at Seo-gu culture center of Kwanju. Control condition for solar cooling and hot water system is changed by connection of auxiliary heater. Demonstration system was connected to central air conditioning system. Demonstration system was operated by two types. First type(A) was operated to cooling and hot water supply in that order. Second type(B) was operated to hot water supply and cooling in that order. As a result. it was indicated that the total solar energy consumption of (A) was 799 MJ and the solar energy consumption rate for the cooling and hot water supply was 70% and 30% respectively. Total solar energy consumption of (b) was 898 MJ and the solar energy consumption rate for the cooling and hot water supply was 31% and 69% respectively.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2011년도 춘계학술발표대회 논문집
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• pp.217-222
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• 2011

This study examined the cooling performance of a solar heating and cooling system for an office building using the dynamic simulation program (TRNSYS). This solar heating and cooling system incorporates evacuated tube solar collectors of $204m^2$, storage tank of $8m^3$, 116.2kW auxiliary heater, single-effect $LiBr/H_2O$ absorption chiller of 20RT nominal cooling capacity. It was found that for the representing day showed peak cooling load the annual average collection efficiency of the collector was 32.9% and coefficient of performance of single-effect $LiBr/H_2O$ absorption chiller was 0.68. And the results shows for the cooling season the solar fraction of the solar heating and cooling system was 32.2% and maximal and minimal solar fraction was 63.4% for May 17.9% for July respectively.

• 태양에너지
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• 제18권2호
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• pp.19-29
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• 1998

국내 소비 에너지 사용량의 약 97%를 수입에 의존하고 있고, 지구온난화와 관련된 환경문제가 심각하게 대두되고 있는 실정이다. 또한 우리나라 에너지 부문별 소비형태에서 47%를 차지하는 산업용의 에너지 소비는 대부분 유류애 의존하고 있고, 그 중에서도 제조부분의 소비가 91.5%로 나타나고 있어, 이 부분에 대체어네지원의 개발, 대체 시스템의 적용이 절실히 요구되고 있다. 우리 나라에서도 국가적 에너지 절약과 쾌적한 주거환경 및 생활의 편리함을 위해 기존 화석에너지로부터 무공해 청정에너지(Clean Energy)로 그 사용형태가 바뀌어 가는 지금 그 양과 질적인 면에서 무한정이고 무공해인 대체 에너지원으로서의 태양에너지는 다양한 이용분야가 개발되어 실용화되고 있다. 국�K의 경우 대표적으로 평판형 태양열집열기를 이용한 온수급탕 시스템을 들 수 있고, 냉난방, 산업공정열 및 태양열 발전 분야에 대한 실용화 및 타당성 연구가 활발히 진행되고 있다. 따라서 본 고에서는 태양열 시스템의 중요한 구성요소인 고효율 집열기술에서 산업용 응용($70{\sim}150^{\circ}C$)에 적합한 것으로 기대되는 진공유리관형 태양열집열기, 국내 외 기술개발 동향과 산업공정열의 대체 가능성에 대하여 기술하였다.

• 한국태양에너지학회 논문집
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• 제32권6호
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• pp.53-59
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• 2012

This study was carried out to evaluate thermal performance of the renewable hybrid heat supply system with solar thermal system and wood pellet boiler for Zero Carbon Green home of apartment houses. The hybrid heat supply system was set up at Korea Institute Energy Research in 2011. The system was comprised of the wood pellet boiler unit with heat capacity designed as 20,000kcal/hr, a $0.15m^3$ hot water storage tank for space heating, a evacuated tubular solar collector $3.74m^2$ of aperture area at the $20^{\circ}$ install angle, a $0.3m^3$ hot water storage tank. Thermal performance tests for one-house of apartment house were carried out by hot water load and heating load in winter season through the hybrid heat supply system. As a result, hot water energy supplied by the hybrid heat supply system was 11kWh in a day. Solar thermal energy portion was 2.99kWh which is 27% of the total hot water energy supply. wood pellet boiler supply portion was 8.017kWh which is 73% of the total hot water energy supply.

• 한국신재생에너지학회:학술대회논문집
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• 한국신재생에너지학회 2005년도 춘계학술대회
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• pp.433-437
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• 2005

This study was carried out the design and analysis of solar thermal system with preheating of returning district heating water for the Chung-ju district heating and cooling system. Two different types of solar collectors are used for this system. TRNSYS simulation program was used for the analysis. As a results, the solar system efficiency is $35.8\%$ for the plate type and $45.1\%$ for the evacuated type solar collector in the case of $50^{\circ}C$ for the returning district heating water temperature. The returning district heating water temperature is on of the very important factors that is influence on the system efficiency. So the effect of the returning district heating water temperature on the system efficiency is analyzed in this study.

• 한국태양에너지학회:학술대회논문집
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• 한국태양에너지학회 2008년도 춘계학술발표대회 논문집
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• pp.203-208
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• 2008

The purpose of this study is to compare the different shapes of condenser of the direct contact heat transfer from the heat pipe condenser to the receiving water using CFD. The heat transfer from the working fluid of the heat pipe to receiving fluid flows through the manifolder is one of the important part in evacuated solar collector system. The retrenchment of the thermal resistance between the heat pipe and the manifolder could increase the thermal performances of the whole system. Recently, direct heat transfer from the heat pipe condenser wall to the receiving water was suggested and accompanied experiments were achieved. This experiment shows the better performances of the direct contact heat transfer analogically. Preceding calculations are carried out for the performance comparison: mesh dependence test, discretization method test and equation model test. with these preceding tests, 4 different shapes of condenser are compared and each case were set up for the same heat flux at the condenser wall. The calculation result shows that the efficiency of the extended surface condenser shape is 10% higher then the that of the others.

• 한국농업기계학회:학술대회논문집
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• 한국농업기계학회 2002년도 동계 학술대회 논문집
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• pp.158-166
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• 2002

진공관형 태양열집열기의 집열성능 및 집열특성 실험을 통하여 다음과 같은 결론을 얻을 수 있었다. 1) 집열성능 실험을 통하여 진공관형 태양열집열기의 순간집열효율이 60%로 높게 나타났다. 2) 진공관형 태양열집열기의 집열특성 실험에 의해 얻어진 결론은 다음과 같다. \circled1 경사각 0$^{\circ}$일 때 집열기에 조사된 광 강도는 630W/m$^2$이었으며, 5시간 24분의 광 조사 후 초기온도에 비해 물탱크내의 물 132$\ell$를 8.1$^{\circ}C$ 상승시켰다. \circled2 경사각 $10^{\circ}$일 때 광강도는 615W/m$^2$이었으며, 5시간 24분의 광 조사 후 초기온도에 비해 물탱크내의 물의 온도를 7.3$^{\circ}C$ 상승시켰다. \circled3 경사각 20$^{\circ}$일 때 광 강도는 605W/m$^2$이었으며, 5시간 24분의 광 조사 후 초기온도에 비해 물탱크의 물 132$\ell$을 6.6$^{\circ}C$ 상승시켰다. 집열기에 대한 솔라시뮬레이터의 경사각이 작을수록 광 강도가 커 물탱크내의 물 온도를 크게 상승시키는 것으로 나타났다.