Experimental Study on Heat Transfer of Single-Phase Flow and Boiling Two-Phase Flow in Vertical Narrow Annuli

Conference · Mon Jul 01 04:00:00 EDT 2002

OSTI ID:21072845

Qiu, Suizheng; Su, Guanghui; Jia, Dounan ^[1]; Takahashi, Minoru ^[2]

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1. Xi'an Jiaotong University, No.28, Xianning West Road, Xi'an, Shaanxi, 710049 (China)
2. Tokyo Institute of Technology, O-okayama, Meguro-ku, Tokyo 152 (Japan)

Water single-phase and nucleate boiling heat transfer were experimentally investigated in vertical annuli with narrow gaps. The experimental data about water single-phase flow and boiling two-phase flow heat transfer in narrow annular channel were accumulated by two test sections with the narrow gaps of 1.0 mm and 1.5 mm. Empirical correlations to predict the heat transfer of the single-phase flow and boiling two-phase flow in the narrow annular channel were obtained, which were arranged in the forms of the Dittus-Boelter for heat transfer coefficients in a single-phase flow and the Jens-Lottes formula for a boiling two-phase flow in normal tubes, respectively. The mechanism of the difference between the normal channel and narrow annular channel were also explored. From experimental results, it was found that the turbulent heat transfer coefficients in narrow gaps are nearly the same to the normal channel in the experimental range, and the transition Reynolds number from a laminar flow to a turbulent flow in narrow annuli was much lower than that in normal channel, whereas the boiling heat transfer in narrow annular gap was greatly enhanced compared with the normal channel. (authors)

• Research Organization: The ASME Foundation, Inc., Three Park Avenue, New York, NY 10016-5990 (United States)
• OSTI ID: 21072845
• Country of Publication: United States
• Language: English

Related Subjects

42 ENGINEERING
CORRELATIONS
HEAT TRANSFER
LAMINAR FLOW
NUCLEATE BOILING
REYNOLDS NUMBER
TUBES
TURBULENT FLOW
TWO-PHASE FLOW
WATER