ITEMS

modern scholarly publishers in the finest tradition

	Search

Annals of the Assembly for International Heat Transfer Conference 13

ISBN 1-56700-225-0 / CD 1-56700-226-9

Volumes per year:

various

Year 2006

DOI: 10.1615/IHTC13.p7

INFLUENCE OF TEMPERATURE ON A WHIRLPOOL FORMATION IN THE COOLING SYSTEM OF A NUCLEAR REACTOR

Mark K. M. Ho
Nuclear Analysis Section, Reactor Operations, Australian Nuclear Science and Technology Organisation, Menai, Australia 2234

Y. A. Stepanyants
Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, Australia

G. Y. Yeoh
Australian Nuclear Science and Technology Organisation (ANSTO), Lucas Heights, Australia

ABSTRACT

Free surface vortices were numerically studied for the modelling of a nuclear reactor cooling system. Two temperature regimes were examined: i) an isothermal case, where the cooling liquid (water) and gas blanket (air) possessed the same temperature, 25 °C, and ii) a non-isothermal case, where there was a temperature gradient between the 50 °C liquid and the 60 °C gas blanket. Dependencies of the whirlpool depth and maximum angular velocity versus time at different flow rates were obtained. In the non-isothermal case, in addition to the central whirlpool, the formation of multiple lateral vortices of relatively large sizes and amplitudes were observed. These additional vortices fluctuated randomly in space and time. In the process of vortex evolution, some spots of irregularly shaped lighter fluid fractions (a mixture of gas and liquid) broke away from the whirlpools and moved towards the downcomer pipe. Thus exhibiting the gas entrainment phenomenon.