Heat transfer model of single-phase natural circulation flow under a rolling motion condition

Experimental studies on heat transfer characteristics for single-phase natural circulation flow under a rolling motion condition are performed. Experiments with and without rolling motions are conducted so that the effects of rolling motion on natural circulation heat transfer are obtained. The experimental results show rolling motion enhances the heat transfer. The heat transfer coefficient of natural circulation flow increases with the rolling amplitude and frequency. A modified Reynolds number that considers the influence of the acceleration is employed to express the effect of heat capacity. Using experimental data, an empirical equation for the heat transfer coefficient under a rolling motion condition is obtained. The calculated results agree with the experimental data. (C) 2009 Elsevier B.V. All rights reserved.