• 제목/요약/키워드: Seawater heat

검색결과 154건 처리시간 0.022초

해수열원 스크류 히트펌프의 연간 난방운전 성능 모사 (A Simulation Study on the Annual Heating Performance of the Seawater-Source Screw Heat Pump)

  • 백영진;김민성;장기창;이영수;김현주
    • 한국태양에너지학회 논문집
    • /
    • 제32권3호
    • /
    • pp.88-95
    • /
    • 2012
  • In this study, in order to utilize the seawater as a heat source at Gangneung city near the East Sea in Korea, an annual heating performance of a screw heat pump was simulated. For a simulation, the maximum heating capacity of heat pump was assumed at 3.5 MW. An ambient temperature at Gangneung city was calculated from the TMY2 weather data, while the seawater temperature was calculated from the regression equation based on the measurement by the National Fisheries Research and Development Institute of Korea. The heating load was assumed linearly dependent on the ambient temperature, while the maximum heating load was assumed to appear when the ambient temperature is below $-2.4^{\circ}C$, which is the temperature of TAC 2.5% for heating at Gangneung city. A heat pump performance at full-load was calculated from the regression equation, which involves refrigerant's evaporating and condensing temperatures, based on a commercial screw compressor performance map. A heating supply temperature which determines refrigerant's condensing temperature was assumed linearly dependent on the heating load. A performance degradation due to the part-load operation of heat pump was also considered. Simulation results show that an annual heating coefficient of performance ($COP_H$) of a seawater-source screw heat pump is approximately 2.8 and that it is necessary to improve part-load performance to increase an annual performance of the heat pump.

해수열원 스크류 히트펌프의 연간 난방운전 성능 시뮬레이션 (A Simulation Study on the Annual Heating Performance of the Seawater-Source Screw Heat Pump)

  • 백영진;김민성;장기창;강병찬;라호상;김현주
    • 한국태양에너지학회:학술대회논문집
    • /
    • 한국태양에너지학회 2012년도 춘계학술발표대회 논문집
    • /
    • pp.488-493
    • /
    • 2012
  • In this study, in order to utilize the seawater as a heat source at Gangneung city near the East Sea in Korea, an annual heating performance of a screw heat pump was simulated. For a simulation, the maximum heating capacity of heat pump was assumed at 3.5 MW. An ambient temperature at Gangneung city was calculated from the TMY2 weather data, while the seawater temperature was calculated from the regression equation based on the measurement by the National Fisheries Research and Development Institute of Korea. The heating load was assumed linearly dependent on the ambient temperature, while the maximum heating load was assumed to appear when the ambient temperature is below $-2.4^{\circ}C$, which is the temperature of TAC 2.5% for heating at Gangneung city. A heat pump performance at full-load was calculated from the regression equation, which involves refrigerant's evaporating and condensing temperatures, based on a commercial screw compressor performance map. A heating supply temperature which determines refrigerant's condensing temperature was assumed linearly dependent on the heating load. A performance degradation due to the part-load operation of heat pump was also considered. Simulation results show that an annual heating coefficient of performance ($COP_H$) of a seawater-source screw heat pump is approximately 2.8 and that it is necessary to improve part-load performance to increase an annual performance of the heat pump.

  • PDF

해수 냉방시스템의 빙상경기장 적용 방안 및 LCC 분석 (Application and Life Cycle Cost Analysis for Ice-rink using Seawater Heat Source Cooling System)

  • 박진영;김삼열;이호생;김현주
    • 한국태양에너지학회 논문집
    • /
    • 제33권2호
    • /
    • pp.50-55
    • /
    • 2013
  • On a plan for the Winter Olympics 2018, Korean government is in the process of the world's first use of ocean energy for the Olympic ice-rink. This technology will be applied to a seaside town and have possibility of an export industry. In this study, we researched facilities and system for P ice-rink that acts as a cultural center as well as a physical plant in Busan and provided the way that apply by seawater heat source. Also, existing system and seawater heat source system of P ice-rink was analyzed by the most commonly used life cycle cost analysis among economics methods. Such economics data for ice-rink using seawater will be utilized by a basic information.

Materials Integrity Analysis for Application of Hyper Duplex Stainless Steels to Korean Nuclear Power Plants

  • Chang, Hyun-Young;Park, Heung-Bae;Park, Yong-Soo;Kim, Soon-Tae;Kim, Young-Sik;Kim, Kwang-Tae;Jhang, Yoon-Young
    • Corrosion Science and Technology
    • /
    • 제9권5호
    • /
    • pp.187-195
    • /
    • 2010
  • Hyper duplex stainless steels have been developed in Korea for the purpose of application to the seawater system of Korean nuclear power plants. This system supplies seawater to cooling water heat exchanger tubes, related pipes and chlorine injection system. In normal operation, seawater is supplied to heat exchanger through the exit of circulating water pump headers, and the heat exchanged sea water is extracted to the discharge pipes in circulating water system connected to the circulating water discharge lines. The high flow velocity of some part of seawater system in nuclear power plants accelerates damages of components. Therefore, high strength and high corrosion resistant steels need to be applied for this environment. Hyper duplex stainless steel (27Cr-7.0Ni-2.5Mo-3.2W-0.35N) has been newly developed in Korea and is being improved for applying to nuclear power plants. In this study, the physical & mechanical properties and corrosion resistance of newly developed materials are quantitatively evaluated in comparative to commercial stainless steels in other countries. The properties of weld & HAZ (heat affected zone) are analyzed and the best compositions are suggested. The optimum conditions in welding process are derived for ensuring the volume fraction of ferrite(${\alpha}$) and austenite(${\gamma}$) in HAZ and controlling weld cracks. For applying these materials to the seawater heat exchanger, CCT and CPT in weldments are measured. As a result of all experiments, it was found that the newly developed hyper duplex stainless steel WREMBA has higher corrosion resistance and mechanical properties than those of super austenitic stainless steels including welded area. It is expected to be a promising material for seawater systems of Korean nuclear power plants.

대형 LNG선 주냉각기 해수라인의 부압현상 해석에 관한 연구 (A Study on the Analysis of a Negative Pressure in the Seawater Line of a Main Centeral Cooler (MCC) for a Large LNG Ship)

  • 김창복;사공운곤;김종규;김충식;송영호;최순호
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제32권6호
    • /
    • pp.893-900
    • /
    • 2008
  • The heat exchangers in the ships have been changed from the conventional shell & tube type to the plate type due to some merits as a compactness, a high thermal efficiency and a light-weight. In recent. it is reported that the vacuum phenomena were occurred in the seawater outlet piping of a main central cooler (MCC) on the ships. From the viewpoints of a common sense, the vacuum pressure in the seawater piping is rare event and difficult to be convinced because the seawater is pumped into the piping by a seawater pump with a high discharge head. However, the occurrence of a vacuum pressure in the seawater line of an MCC is real situation and often gives a severe damage to a rubber gasket of an MCC with a plate type heat transfer area. In this study, we analyzed the vacuum pressure in the seawater line of an MCC by using the simpl Bernoulli's equation and found that the vacuum pressure in the seawater line of an MCC is inevitable untill the installation postion of an MCC is not lowered.

폐열 이용 폐쇄형 해양온도차발전 사이클의 성능 (Performance Analysis of Closed-type OTEC Cycle using Waste Heat)

  • 이호생;정동호;홍석원;김현주
    • 한국해양공학회지
    • /
    • 제25권1호
    • /
    • pp.80-84
    • /
    • 2011
  • The cycle performance of closed ocean thermal energy conversion (OTEC) system with 50 kW gross power was evaluated to obtain the basic data for the optimal design of OTEC using waste heat such as solar power, discharged heat from condenser of power plant. The basic thermodynamic model for OTEC is Rankine cycle, and the surface seawater and deep seawater were used for the heat source of evaporator and condenser, respectively. The cycle performance such as efficiency, heat exchanger capacity, etc. was analyzed on the variation of temperature increase by waste heat. The cycle efficiency increased and necessary capacity of evaporator and condenser decreased under 50kW gross power with respect to the temperature increase of working fluid. Also, when the temperature increase is about $13.5^{\circ}C$, the heat which can be used is generated. By generator with 0.9 effectiveness under the simulated condition, the cycle efficiency was improved approximately 3.0% comparing with the basic cycle.

해수냉각시스템용 Aluminium Brass Tube의 R-134a 증발열전달 특성 (Evaporating heat transfer characteristics of Aluminum-brass tube for seawater cooling system using R-134a)

  • 강인호;설성훈;윤정인;손창효
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제41권3호
    • /
    • pp.197-201
    • /
    • 2017
  • 대부분의 어선에서는 포획된 어류를 관리하고 저장하기 위해 얼음 냉각 시스템을 사용한다. 그러나 얼음 냉각 시스템은 작동 시간의 제한뿐만 아니라 적절한 온도와 염분 농도를 유지하는 것이 어려운 단점이 있다. 본 연구의 목적은 어류 운반선의 어창에 적정한 해수온도 유지를 위한 해수 냉각 시스템용 만액식 증발 열전달 특성을 파악하는데 있다. 실험은 냉매의 해수 온도, 유량 및 포화 온도의 변화를 주며 열전달 특성을 파악하였다. 동일 열유속에서 Aluminium-Brass tube가 Copper-Nickel tube 보다 외측 열전달계수가 약 10% 큰 것으로 확인할 수 있었으며, 이를 통해 해수용 열교환기의 전열관으로 Aluminium-Brass를 적용하는 것이 열전달 측면에서 효과적일 것을 확인할 수 있었다. 만액식 단관 열전달계수와 18 kW급 만액식 해수냉각시스템의 총괄열전달계수의 비교를 통해 동일 조건에서는 25%정도 단관의 열전달계수가 큰 값을 나타내었으며, 이러한 결과는 만액식 관군 열교환기의 설계를 위한 중요한 자료가 되리라 판단된다.

해수 열원 및 폐열 이용 고성능 열펌프 시스템 모사 (Simulation for High Efficient Heat Pump System using Seawater Heat Source and Exhaust Energy)

  • 최광일;오종택;오후규
    • 설비공학논문집
    • /
    • 제15권1호
    • /
    • pp.59-66
    • /
    • 2003
  • The purpose of this study is to analyze the characteristics (COP) of the heat pump system for various operating conditions with the use of seawater heat source and exhaust energy. To accomplish the goal, first of all, the computer simulation for heat pump system is carried out. The heat pump system model is made of a waste heat recovery system and a vapor compression refrigeration system, and the working fluid is R-22. The model calculated the change of COP with the variation of temperature and flow rate. The COP and the plate heat exchanger (PHE) area of the heat pump system are considered moderately high in the condensation temperature of $25^{\circ}^C$ and the evaporation temperature of $2^{\circ}^C$ in indoor culture system. The simulation results will be used effectively for the design and the performance prediction of heat pump system using unused energy in a land base aquaculture system.

진공열전달기술에 의한 해수의 종합자원화에 관한 연구 (A study on the comprehensive resources utilization of seawater by the vacuum heat transfer technology)

  • 소예덕;문수범;김경근;최부홍;이서연
    • Journal of Advanced Marine Engineering and Technology
    • /
    • 제39권7호
    • /
    • pp.685-695
    • /
    • 2015
  • 바닷물을 농축하면 농도가 높아짐에 따라서 뻘과 산화철, 석고, 소금, 미네랄, 용존광물이 순차적으로 석출된다. 이 논문에서는 이러한 해수의 물리적 특성을 이용하여, 해수 중의 용존성분들을 순차적으로 석출하여 회수할 수 있는 경제성 있는 새로운 진공열전달기술을 제안하였다. 진공상태하의 열전달특성에 관한 실험적 결과를 토대로 해수 종합자원화를 위한 공정을 다음과 같이 4-공정으로 구분하였다. 즉, (1)소금이 석출되기 시작하는 포화농도까지의 농축하는 단계, (2)소금의 결정화가 이루어지는 단계, (3)미네랄이 석출되는 단계, (4)잔류 용존금속 액체의 4-공정이다.

해수열원을 이용한 빙상경기장의 에너지절약 방안에 관한 연구 (Energy Saving Strategies for Ice Rink using Sea-Water Heat Source Cooling System)

  • 김삼열;박진영;박재홍
    • 한국태양에너지학회 논문집
    • /
    • 제34권2호
    • /
    • pp.53-59
    • /
    • 2014
  • Ice Rink is energy intensive building type. Concern of energy saving from buildings is one of very important issues nowadays. New and renewable energy sources for buildings are especially important when we concern about energy supply for buildings. Among new and renewable energy sources, use of seawater for heating and cooling is an emerging issue for energy conscious building design. The options of energy use from sea water heat sources are using deep sea water for direct cooling with heat exchange facilities, and using surface layer water with heat pump systems. In this study, energy consumptions for an Ice Rink building are analyzed according to the heat sources of air-conditioning systems; existing system and sea water heat source system, in a coastal city, Kangnung. The location of the city Kangnung is good for using both deep sea water which is constant temperature throughout the year less than $2^{\circ}C$, and surface layer water which should be accompanied with heat pump systems. The result shows that using sea water from 200m and 30m under sea lever can save annual energy consumption about 33% of original system and about 10% of that using seawater from 0m depth. Annual energy consumption is similar between the systems with seawater from 200m and 30m. Although the amount of energy saving in summer of the system with 200m depth is higher than that with 30m depth, the requirement of energy in winter of the system with 200m depth is bigger than that with 30m depth.