한국가시화정보학회지 (Journal of the Korean Society of Visualization)

  • 제19권3호
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  • Pages.99-105
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  • 2021
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  • 1598-8430(pISSN)
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  • 2093-808X(eISSN)
한국가시화정보학회 (The Korean Society of Visualization)
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디퓨저 타입 계간 축열조 내부 열성층화에 대한 입구 유속 및 탱크 종횡비 영향 연구

Effects of the aspect ratio and inlet velocity on the thermal stratification in a diffuser type seasonal thermal storage tank

  • Kim, Seong Keun (Department of Mechanical Engineering, Chosun University) ;
  • Jung, Sung Yong (Department of Mechanical Engineering, Chosun University)
  • 투고 : 2021.11.06
  • 심사 : 2021.12.16
  • 발행 : 2021.12.31
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초록

In this study, the thermal stratification in solar seasonal thermal storage tanks was numerically simulated. The effects of the aspect ratio (AR) and inlet velocity on the thermal stratification in the diffuser type heat storage tank were investigated. The temperature distributions inside the tank were similar with velocity fields. Jet flows from opposite diffusers encountered each other at the tank center region. Thereafter, the downward flows occurred, and this flows strongly affected the thermal stratification. When AR was smaller than 2, these downward flows influenced a further distance and enhanced mixing inside the tank. Thermal stratification was evaluated by thermocline thickness and degree of stratification, and AR of 3 had the highest degree of stratification. The inlet velocity effect was expressed with the ratio (Re/Ri) of Reynolds and Richardson numbers. The second-order approximation was found for the relationship between the thermocline thickness and log Re/Ri.

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과제정보

본 연구는 과학기술정보통신부의 재원으로 한국연구재단의 지원을 받아 수행되었습니다(NRF-2020R1C1C1004344).

참고문헌

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