文档介绍：Cryogenics 52 (2012) 268–277
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Cryogenics
journal homepage: ate/cryogenics
An experimental study on flow patterns and heat transfer characteristics
during cryogenic chilldown in a vertical pipe
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Hong Hu a, , Jacob N. Chung a, Samuel H. Amber b
a Department of Mechanical and Aerospace Engineering, University of Florida, Gainesville, Florida 32611, United States
b Department of Physics and Nuclear Engineering, . Military Academy, West point, New York 10928, United States
article info abstract
Article history: In the present paper, the experimental results of a cryogenic chilldown process are reported. The physical
Available online 6 March 2012 phenomena involve unsteady two-phase vapor–liquid flow and intense boiling heat transfer of the cryo-
genic fluid that is coupled with the transient heat conduction inside pipe walls. The objective for the pres-
Keywords: ent study is pare the chilldown rates and flow patterns between the upward flow and downward
Cryogenics flow in a vertical pipe. Liquid nitrogen is employed as the working fluid and the test section is a vertical
Quenching straight segment of a Pyrex glass pipe with an inner diameter of 8 mm. The effects of mass flow rate on
Flow boiling
the flow patterns, heat transfer characteristics and interface movement were determined through exper-
Heat transfer