Journal of the Korean Society of Visualization (한국가시화정보학회지)

The Korean Society of Visualization (한국가시화정보학회)
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Effect of an aspect ratio on thermal stratification in a solar seasonal thermal storage tank

태양열 계간 축열조 내부 열성층화에 대한 탱크 종횡비 영향 연구

  • Kim, Seong Keun (Department of Mechanical Engineering, Chosun University) ;
  • Jung, Sung Yong (Department of Mechanical Engineering, Chosun University)
  • Received : 2020.07.14
  • Accepted : 2020.08.26
  • Published : 2020.08.31
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Abstract

In this study, we numerically investigated the thermal stratification in solar seasonal thermal storage tanks. The vertical in/out flows were unsuitable for the thermal stratification in a large scale. The effect of an aspect ratio (AR) on the thermal stratification was investigated. When AR was less than 2, water adheres and flows along the upper wall due to buoyance and the surface effect. Thereafter, hot water flows down and a large scale vortex occurs in entire tank. For high AR, jet flows ejected from the inlet pipe impinges to the opposite wall and splits. The divided flows create two vortex flows in the upper and lower regions. These different flows strongly influence temperature and thermal stratification. The thermal stratification was evaluated in terms of the thermocline thickness and degree of stratification. Compared to ARs, the maximum degree of stratification was obtained with AR of 5 having the minimum thermocline thickness.

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References

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