Transactions of the Korean Society of Mechanical Engineers B (대한기계학회논문집B)

The Korean Society of Mechanical Engineers (대한기계학회)
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Computational Fluid Dynamics Model for Solar Thermal Storage Tanks with Helical Jacket Heater and Upper Spiral Coil Heater

상부 코일히터를 갖춘 나선재킷형 태양열 축열조의 성능예측을 위한 CFD 해석모델 개발 및 검증

  • Baek, Seung Man (Sch. of Mechanical and Aerospace Eng., Seoul Nat'l Univ.) ;
  • Zhong, Yiming (Sch. of Mechanical and Automotive Eng., Daegu Univ.) ;
  • Nam, Jin Hyun (Sch. of Mechanical and Automotive Eng., Daegu Univ.) ;
  • Chung, Jae Dong (Sch. of Mechanical and Aerospace Eng., Sejong Univ.) ;
  • Hong, Hiki (Dept. of Mechanical Eng., Kyung Hee Univ.)
  • 백승만 (서울대학교 기계항공공학부) ;
  • 종일명 (대구대학교 기계자동차공학부) ;
  • 남진현 (대구대학교 기계자동차공학부) ;
  • 정재동 (세종대학교 기계항공우주공학부) ;
  • 홍희기 (경희대학교 기계공학과)
  • Received : 2012.06.07
  • Accepted : 2013.01.08
  • Published : 2013.04.01
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Abstract

In a solar domestic hot water (SDHW) system, solar energy is collected using collector panels, transferred to a circulating heat transfer fluid (brine), and eventually stored in a thermal storage tank (TST) as hot water. In this study, a computational fluid dynamics (CFD) model was developed to predict the solar thermal energy storage in a hybrid-type TST equipped with a helical jacket heater (mantle heat exchanger) and an immersed spiral coil heater. The helical jacket heater, which is the brine flow path attached to the side wall of a TST, has advantages including simple system design, low brine flow rate, and enhanced thermal stratification. In addition, the spiral coil heater further enhances the thermal performance and thermal stratification of the TST. The developed model was validated by the good agreement between the CFD results and the experimental results performed with the hybrid-type TST in SDHW settings.

태양열 온수급탕 시스템에서는 태양열 에너지가 집열판에서 획득되고 열매체로 전달되어 최종적으로 온수의 형태로 축열조에 저장된다. 본 연구에서는 상부 코일히터를 갖춘 나선재킷형 축열조의 축열성능 특성을 정확하게 해석할 수 있는 전산유체역학 모델을 개발하였다. 본 연구에서 고려한 축열조는 벽면에 열매체의 나선유로가 형성된 맨틀형 축열조의 일종으로 시스템 설계 단순화, 저유량 운전, 성층화 촉진 등의 장점을 지닌다. 또한 축열조 내부에 추가적인 코일히터가 장착되어 축열성능과 성층화의 추가적인 향상을 도모할 수 있다. 본 연구에서 개발된 해석모델의 검증은 실제 태양열 온수급탕 시스템의 실증실험 결과와 비교를 통하여 수행되었으며, 온수의 온도변화, 열매체의 온도변화, 성층화 온도분포의 측면에서 잘 일치하는 결과를 얻었다.

Keywords

References

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