• 제목/요약/키워드: water heating

검색결과 1,969건 처리시간 0.022초

열원 및 부하조건에 따른 물-공기 히트펌프 시스템의 성능분석 (Performance Analysis of Water-to-Air Heat Pump System under Water Temperature and Load Ratio)

  • 조용;이동근
    • 한국신재생에너지학회:학술대회논문집
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    • 한국신재생에너지학회 2011년도 춘계학술대회 초록집
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    • pp.194.2-194.2
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    • 2011
  • Heating and cooling performance has been analyzed for the water-source heat pump system using raw water from Daechung reservoir. During heating operation from March to May, water temperature is not good condition for a heat source due to the higher atmospheric temperature. Avearged heating load ratio is only 14.3%, and the averaged unit COP and system COP are estimated to be 2.46 and 2.15 respectively. The COP is affected considerably by the water temperature, and the unit COP is increased from 2.16 at $5^{\circ}C$ to 2.95 at $11^{\circ}C$. Cooling performance is analyzed with the measured data from June to August. During cooling operation, raw water has lower temperature by 4. $5^{\circ}C{\sim}4.7^{\circ}C$ than the atmosphere. The load ratio is 39.2%, and the averaged unit COP and system COP are estimated to be 7.25 and 6.13 respectively. The heating COP is affected by the load ratio rather than water temperature. The COP is increased for 20%~40% load ratio, while is decreased for 40%~60% load ratio. It is estimated that the compressor operation combination for 3 (two constant speed and one inverter) compressors is changed for the load ratio.

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한국형 아파트의 난방에너지 분석 2: 난방방식에 따른 차이 (Analysis of Heating Energy in a Korean-Style Apartment Building 2: The Difference according to Heating Type)

  • 이봉진;정동열;이선;홍희기
    • 설비공학논문집
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    • 제16권5호
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    • pp.459-466
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    • 2004
  • In order to save the energy in apartment houses, it is essential that the energy amount consumed in heating per household should be surveyed and analyzed according to heating method, which can be classified into unit, central and district methods. As a basis, we selected the household with nominal area of 32 py. because it accounts for the most percentage in Korea. It is estimated that the gas amount for cooking is 90 ㎥ and the energy amount for hot water supply is 11.41 GJ for a year, which is necessary to calculate the heating energy. Through the survey of actual energy consumption in Seoul and Gyeonggi, the energy amount used in heating can be obtained according to the heating type: 26.02 GJ/year for the unit heating, 28.09 GJ/year for the central heating and 40.61 GJ/year for the district heating.

LiCl-$CaCl_2-Zn(NO_3)_2$ 수용액을 사용하는 흡수 2중효용 시스템에서 태양열을 증발기 열원으로 사용하는 난방기의 열역학적 해석 (Thermodynamic Analysis of a Double-Effect Absorption Heating System Using Water-LiCl-$CaCl_2-Zn(NO_3)_2$ Solution at Solar Evaporator Heating)

  • 원승호
    • 한국태양에너지학회 논문집
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    • 제27권3호
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    • pp.87-94
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    • 2007
  • In this paper, with water-LiCl-$CaCl_2-Zn(NO_3)_2$ mixture which utilizes solar energy at the evaporator heat source, a thermodynamic analysis was performed to provide design data for a double-effect absorption heating system. A comparative study of the water-LiCl-$CaCl_2-Zn(NO_3)_2$ mixture against the water-LiBr pair was conducted by a computer simulation. The computer simulation is based on mass, material and heat balance equations for each part of the system. Coefficients of performance and flow ratios for effects of different operating temperatures are investigated. It is found that the heating COP is higher for the water-LiCl-$CaCl_2-Zn(NO_3)_2$ mixture than for the water-LiBr pair, and FR is lower for the former.

태양열을 증발기 열원으로 사용($20{\sim}40^{\circ}C$범위)하며 LiSCN+LiBr 수용액을 사용하는 흡수식 2중효용 난방시스템의 열역학적 해석 (Thermodynamic Analysis of a Double-Effect Absorption Heating System Using Water-LiBr- LiSCN Solution As $20{\sim}40^{\circ}C$ Range Solar Evaporator Heating)

  • 원승호
    • 한국태양에너지학회 논문집
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    • 제26권4호
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    • pp.73-81
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    • 2006
  • In this paper, with water-LiBr-LiSCN mixture which utilizes solar energy as mid temperature range evaporator heat source, a thermodynamic analysis was performed to provide design data for a double-effect absorption heating system. A comparative study of the water-LiBr-LiSCN mixture against the water-LiBr pair was conducted by a computer simulation. The computer simulation is based on mass, material and heat balance equations for each part of the system. Coefficients of performance and flow ratios for effects of different operating temperatures are investigated. It is found that the heating COP is higher for the water-LiBr-LiSCN mixture than for the water-LiBr pair, and FR is lower for the former.

태양열 온수 및 난방 일체형 복합시스템의 성능예측 (Performance Prediction of a Hot Water Supply and Panel Heating System with Solar Energy)

  • 한유리;박윤철
    • 한국태양에너지학회 논문집
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    • 제32권5호
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    • pp.11-17
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    • 2012
  • In this study, a simulation program was developed with heat transfer model in the thermal storage tank for a solar collector and burner combined heating and hot water supply system. Analysis was conducted with variation of operating condition and schedule to analyze performance of a hot water supply and panel heating system with a solar collector and burner combined thermal storage tank. The simulation program is divided two sections. One part is calculation of temperature variation of water which flows through the panel in the floor for heating of the residential house during 24 hours, and the other part is heat transfer calculation for the reaction time to get desired water temperature in the thermal storage tank. As results, light oil consumption and system performance during operation period were analyzed with variation of climate condition and with or without solar collector. Most of the case, oil could be saved about from 24 to 41% with installing the solar collector. The performance of the system is more dependent on radiation time of the solar collector rather than the intensity of the solar radiation which was adopted for the climate analysis.

난방부하와 온수온돌의 방열성능을 고려한 적정 공급온수온도 산출방법에 관한 연구 (A Study on the Method of Estimating Optimum Supply Water Temperature Considering the Heating Load and the Heat Emission Performance of Radiant Floor Heating Panel)

  • 최정민;이규남;류성룡;김용이;여명석;김광우
    • 대한설비공학회:학술대회논문집
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    • 대한설비공학회 2006년도 하계학술발표대회 논문집
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    • pp.795-800
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    • 2006
  • A common approach to achieve better thermal comfort with hydronic radiant floor heating system is supply water temperature control. This is the control method through which supply water temperature is varied with outdoor temperature. In this study, a comprehensive, yet simple calculation method to find optimum supply water temperature is evaluated by combining heat loss from the building and heat emission from the hydronic radiant floor heating system. And then the control performance of suggested calculation method is confirmed through experiment. It is shown that indoor air temperature is stably maintained around the set point.

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실내수영장의 에너지 소비요소별 에너지 절약효과에 관한 연구 (A Study on the Energy Conservation Effect of Each Energy Consumption Component In Indoor Swimming Pools)

  • 김영돈;권규동;여명석;김광우
    • 설비공학논문집
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    • 제14권12호
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    • pp.1092-1101
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    • 2002
  • The objective of this study is to develop energy saving strategies for indoor swimming pools and to estimate the effect of each energy saving strategy. For this purpose, field measurements regarding pool water heating energy, domestic hot water heating energy are conducted and a base energy consumption model is implemented using the DOE-2.1E program. The results of the study reveal that 25% of the total pool water heating energy may be saved by using night time pool covers, 27% of the total domestic hot water heating energy may be saved by using a waste water heat recovery system (effic. 60%), and of the total ventilation energy may be saved using an exhaust air heat recovery system (effic. 60%).

PTC 전열시트를 사용한 핀-관 열교환기의 제상 특성에 관한 실험적 연구 (An experimental study of defrosting behaviors on the fin-tube heat exchanger with PTC heating sheet)

  • 지성;이관수
    • 설비공학논문집
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    • 제11권1호
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    • pp.147-155
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    • 1999
  • In this work, the defrosting characteristics of PTC heating sheet used as a defrosting heat source of fin-tube heat exchanger in a refrigerator have been experimentally compared with those of conventional electric heater. It is found that the characteristics of water draining rate with defrosting time show smoothly oscillating pattern when PTC heating sheet is used, and the drained water is completely melted. The defrosting efficiency of the PTC heating sheet is about 75%, which represents about 25% higher than that of the electric heater. A reduction of defrosting time and an increase of defrosting efficiency may be obtained by improving the arrangement of heating elements of the heating sheet. It is shown that the defrosting time of PTC heating sheet increases linearly with the amount of frost, however the defrosting efficiency is nearly constant. In the application to the refrigerating system, one should notice the fact that the defrosting performance of PTC heating sheet may be defraded due to the repeated operations.

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유출지하수 열원 지열히트펌프시스템의 난방성능 (Heating Performance of Ground source Heat Pump using Effluent Ground Water)

  • 박근우;이응열
    • 신재생에너지
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    • 제3권2호
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    • pp.40-46
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    • 2007
  • Effluent ground water overflow in deep and broad ground space building. Temperature of effluent ground water is in $12{\sim}20^{\circ}...$ annually and the quality of that water is as good as well water. Therefore if the flow rate of effluent ground water is sufficient as source of heat pump, that is good heat source and heat sink of heat pump. Effuent ground water contain the thermal energy of surrounding ground. So this is a new application of ground source heat pump. In this study open type and close type heat pump system using effluent ground water was installed and tested for a church building with large and deep ground space. The effluent flow rate of this building is $800{\sim}1000\;ton/day$. The heat pump capacity is 5RT. The heat pump heating COP was $3.85{\sim}4.68$ for the open type and $3.82{\sim}4.69$ for the close type system. The system heating COP including pump power is $3.0{\sim}3.32$ for the open type and $3.32{\sim}3.84$ for close type system. This performance is up to that of BHE type ground source heat pump.

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전자제어 장치를 이용한 세라믹 파이프의 온수제어기 개발 (A Controller Development of Water Heating in a Ceramic Pipe Using Electronics Control System)

  • 이정석
    • 한국전자통신학회논문지
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    • 제6권5호
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    • pp.717-722
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    • 2011
  • 본 논문은 원통형 세라믹관에서 온수를 순간적으로 가열하여 설정된 온도 및 수량으로 제어하고자 전자 제어기를 개발하였다. 순간온수기의 구조는 유입되는 온수가 원통형 세라믹 히터를 통하여 열량을 공급하여 온도를 제어하고자 설계하였고, 또한 수량센서와 임펠러를 이용한 수량을 제어하는 전자 제어기를 설계하였다. 순간온수의 제어방법은 유입되는 유량에 열량을 공급하는 원통형 세라믹 히터의 수학적인 모델링을 수립하여 제어기 적용하였고, 이에 대한 실험결과는 설정온도에 따라 제어가 잘 적용되어, 효율적이고 실용성 결과를 보였다. 따라서 원통형 세라믹 순간온수기는 향후 실용제품에 적용할 수 있는 제품구조와 제어 방법을 제시하였다.