Bubble behaviour and mean diameter in subcooled flow boiling

Conference · Fri Sep 01 04:00:00 EDT 1995

OSTI ID:111455

Zeitoun, O; Shoukri, M ^[1]

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1. McMaster Univ., Hamilton, Ontario (Canada)

Bubble behaviour and mean bubble diameter in subcooled upward flow boiling in a vertical annular channel were investigated under low pressure and mass flux conditions. A high speed video system was used to visualize the subcooled flow boiling phenomenon. The high speed photographic results indicated that, contrary to the common understanding, bubbles tend to detach from the heating surface upstream of the net vapour generation point. Digital image processing technique was used to measure the mean bubble diameter along the subcooled flow boiling region. Data on the axial area-averaged void fraction distributions were also obtained using a single beam gamma densitometer. Effects of the liquid subcooling, applied heat flux and mass flux on the mean bubble size were investigated. A correlation for the mean bubble diameter as a function of the local subcooling, heat flux and mass flux was obtained.

• Research Organization: Nuclear Regulatory Commission, Washington, DC (United States). Div. of Systems Technology; American Nuclear Society, La Grange Park, IL (United States); American Inst. of Chemical Engineers, New York, NY (United States); American Society of Mechanical Engineers, New York, NY (United States); Canadian Nuclear Society, Toronto, ON (Canada); European Nuclear Society (ENS), Bern (Switzerland); Atomic Energy Society of Japan, Tokyo (Japan); Japan Society of Multiphase Flow, Kyoto (Japan)
• OSTI ID: 111455
• Report Number(s): NUREG/CP--0142-Vol.4; CONF-950904--Vol.4; ON: TI95017080
• Country of Publication: United States
• Language: English

Related Subjects

22 GENERAL STUDIES OF NUCLEAR REACTORS
42 ENGINEERING
BOILERS
BUBBLES
FLOW VISUALIZATION
FLUID MECHANICS
HEAT EXCHANGERS
HEAT TRANSFER
HYDRAULICS
REACTOR COOLING SYSTEMS
REFRIGERATING MACHINERY
SUBCOOLED BOILING
TWO-PHASE FLOW
VOID FRACTION