中国物理B ›› 2019, Vol. 28 ›› Issue (9): 94701-094701.doi: 10.1088/1674-1056/ab343d

• ELECTROMAGNETISM, OPTICS, ACOUSTICS, HEAT TRANSFER, CLASSICAL MECHANICS, AND FLUID DYNAMICS • 上一篇    下一篇

Strong coupling between height of gaps and thickness of thermal boundary layer in partitioned convection system

Ze-Peng Lin(林泽鹏), Yun Bao(包芸)   

  1. Department of Mechanics, Sun Yat-Sen University, Guangzhou 510275, China
  • 收稿日期:2019-04-14 修回日期:2019-06-03 出版日期:2019-09-05 发布日期:2019-09-05
  • 通讯作者: Yun Bao E-mail:stsby@mail.sysu.edu.cn
  • 基金资助:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11772362 and 11452002) and the Special Scientific Research Fund for Super Computing in the Joint Fund of the National Natural Science Foundation of China and the People's Government of Guangdong Province, China (Phase II, nsfc2015_570).

Strong coupling between height of gaps and thickness of thermal boundary layer in partitioned convection system

Ze-Peng Lin(林泽鹏), Yun Bao(包芸)   

  1. Department of Mechanics, Sun Yat-Sen University, Guangzhou 510275, China
  • Received:2019-04-14 Revised:2019-06-03 Online:2019-09-05 Published:2019-09-05
  • Contact: Yun Bao E-mail:stsby@mail.sysu.edu.cn
  • Supported by:

    Project supported by the National Natural Science Foundation of China (Grant Nos. 11772362 and 11452002) and the Special Scientific Research Fund for Super Computing in the Joint Fund of the National Natural Science Foundation of China and the People's Government of Guangdong Province, China (Phase II, nsfc2015_570).

摘要:

A direct numerical simulation (DNS) method is used to calculate the partitioned convection system with Ra number ranging from 107 to 2×109. Using the boundary layer thickness to normalize the height of gaps d, we find a strong consistency between the variation of the TD number (the average value of the temperature in each heat transfer channel is averaged after taking the absolute values) with the change of the height of gaps and the variation of the TD number with the change of Ra number in partitioned convection. For a given thickness of partition, heights of gaps are approximately equal to 0.5 or 1 time of the thermal boundary layer thickness λθ at different Ra numbers. TD number representing temperature characteristics is almost the constant value, which means that TD number is a function of d/λθ only. Analysis of local temperature field of area in gaps shows that the temperature distribution in the gaps are basically the same when d/λθ is certain. The heat transfer Nu number of the system at d/λθ≈ 0.5 is larger than that of d/λθ≈ 1, both of them have the same scaling law with Ra number and Nu~Ra0.25.

关键词: partitioned convection system, height of gaps, thermal boundary layer, TD number

Abstract:

A direct numerical simulation (DNS) method is used to calculate the partitioned convection system with Ra number ranging from 107 to 2×109. Using the boundary layer thickness to normalize the height of gaps d, we find a strong consistency between the variation of the TD number (the average value of the temperature in each heat transfer channel is averaged after taking the absolute values) with the change of the height of gaps and the variation of the TD number with the change of Ra number in partitioned convection. For a given thickness of partition, heights of gaps are approximately equal to 0.5 or 1 time of the thermal boundary layer thickness λθ at different Ra numbers. TD number representing temperature characteristics is almost the constant value, which means that TD number is a function of d/λθ only. Analysis of local temperature field of area in gaps shows that the temperature distribution in the gaps are basically the same when d/λθ is certain. The heat transfer Nu number of the system at d/λθ≈ 0.5 is larger than that of d/λθ≈ 1, both of them have the same scaling law with Ra number and Nu~Ra0.25.

Key words: partitioned convection system, height of gaps, thermal boundary layer, TD number

中图分类号:  (Turbulent convective heat transfer)

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