Turbulent heat transfer characteristics of supercritical n-decane in a vertical tube under various operating pressures
(2019) In International Journal of Energy Research 43(9). p.4652-4669- Abstract
To explore the effect of the operating pressure on the flow and thermal characteristics in a vertical tube with supercritical n-decane, the inner wall temperature along the streamwise direction, the applicability of empirical correlations and buoyancy criteria are studied firstly. The mechanisms in views of density distribution, velocity field, turbulence intensity, the thickness of the thermal boundary layer, and secondary flow are then analyzed. It is observed that the buoyancy is helpful for the phenomenon of heat transfer deterioration at lower operating pressures but higher operating pressures can diminish this tendency. According to this reason, the empirical correlation proposed by Bae and Kim is suitable for the higher operating... (More)
To explore the effect of the operating pressure on the flow and thermal characteristics in a vertical tube with supercritical n-decane, the inner wall temperature along the streamwise direction, the applicability of empirical correlations and buoyancy criteria are studied firstly. The mechanisms in views of density distribution, velocity field, turbulence intensity, the thickness of the thermal boundary layer, and secondary flow are then analyzed. It is observed that the buoyancy is helpful for the phenomenon of heat transfer deterioration at lower operating pressures but higher operating pressures can diminish this tendency. According to this reason, the empirical correlation proposed by Bae and Kim is suitable for the higher operating pressures but cannot well predict the occurrence of heat transfer deterioration. However, it can be evaluated by the buoyancy criterion Gr/Re2 = 0.01 qualitatively. The decrease of turbulence intensity, the thickened thermal boundary layer, and secondary flow generation make contributions to the heat transfer deterioration in particular. Similarly, this situation can be diminished and even removed by the higher operating pressures.
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- author
- Li, Yong ; Sun, Feng ; Sunden, Bengt LU and Xie, Gongnan LU
- organization
- publishing date
- 2019-05-23
- type
- Contribution to journal
- publication status
- published
- subject
- keywords
- buoyancy, operating pressure, secondary flow, supercritical n-decane, thermal boundary layer, turbulence intensity
- in
- International Journal of Energy Research
- volume
- 43
- issue
- 9
- pages
- 4652 - 4669
- publisher
- John Wiley & Sons Inc.
- external identifiers
-
- scopus:85066885621
- ISSN
- 0363-907X
- DOI
- 10.1002/er.4602
- language
- English
- LU publication?
- yes
- id
- 2ac1110c-b42a-44ae-9bc2-9b4fbab1f6fb
- date added to LUP
- 2019-06-25 12:15:00
- date last changed
- 2022-04-26 02:01:44
@article{2ac1110c-b42a-44ae-9bc2-9b4fbab1f6fb,
abstract = {{<p>To explore the effect of the operating pressure on the flow and thermal characteristics in a vertical tube with supercritical n-decane, the inner wall temperature along the streamwise direction, the applicability of empirical correlations and buoyancy criteria are studied firstly. The mechanisms in views of density distribution, velocity field, turbulence intensity, the thickness of the thermal boundary layer, and secondary flow are then analyzed. It is observed that the buoyancy is helpful for the phenomenon of heat transfer deterioration at lower operating pressures but higher operating pressures can diminish this tendency. According to this reason, the empirical correlation proposed by Bae and Kim is suitable for the higher operating pressures but cannot well predict the occurrence of heat transfer deterioration. However, it can be evaluated by the buoyancy criterion Gr/Re<sup>2</sup> = 0.01 qualitatively. The decrease of turbulence intensity, the thickened thermal boundary layer, and secondary flow generation make contributions to the heat transfer deterioration in particular. Similarly, this situation can be diminished and even removed by the higher operating pressures.</p>}},
author = {{Li, Yong and Sun, Feng and Sunden, Bengt and Xie, Gongnan}},
issn = {{0363-907X}},
keywords = {{buoyancy; operating pressure; secondary flow; supercritical n-decane; thermal boundary layer; turbulence intensity}},
language = {{eng}},
month = {{05}},
number = {{9}},
pages = {{4652--4669}},
publisher = {{John Wiley & Sons Inc.}},
series = {{International Journal of Energy Research}},
title = {{Turbulent heat transfer characteristics of supercritical n-decane in a vertical tube under various operating pressures}},
url = {{http://dx.doi.org/10.1002/er.4602}},
doi = {{10.1002/er.4602}},
volume = {{43}},
year = {{2019}},
}