Nuclear Techniques ›› 2018, Vol. 41 ›› Issue (7): 70601-070601.

• NUCLEAR PHYSICS, INTERDISCIPLINARY RESEARCH •

### Experimental study on natural convective heat transfer with bottom curved heating surface in a rectangular enclosure

YAO Jun1, CHEN Bin1,2, JIAO Shouhua1, CHAI Xiang1, YANG Yanhua1

1. 1. Shanghai Jiao Tong University, Shanghai 200240, China;
2. Nuclear Power Institute of China, Chengdu 610213, China
• Received:2018-02-07 Revised:2018-04-20 Online:2018-07-10 Published:2018-07-07
• Supported by:
Supported by Science and Technology on Reactor System Design Technology Laboratory (No.HT-KFKT-02-2016001)

Abstract: [Background] In the design of some small modular reactor (SMR), the upper head of containment vessel is immersed in a large amount of coolant. After a severe accident, the residual heat inside containment vessel is then removed by natural convection above the upper head. [Purpose] This study aims to undertake research into the two-dimensional natural convective heat transfer above the upper head of containment vessel and the flow field around it. [Methods] A rectangular enclosure device with bottom curved heating surface was utilized to perform experiments under normal pressure. Particle image velocimetry (PIV) technique was employed to measure flow field. [Results] The average Nu number, local heat transfer intensity, velocity field due to curved heating surface were obtained and analyzed. [Conclusion] The average Nu number rises as heating power increases, while the growth rate has a descending trend. Along curved heating surface, local heat transfer intensity decreases first and then increases, lowest value of which occurs near 40° position of curved heating surface. Flow field around curved heating surface is visually revealed. Flow stratification becomes obvious near bulk flow, and the trend after X=50 mm is reverse. Stratification is mainly due to the horizontal component of velocity. The maximum velocity is irrelevant to heating power, whose major influence lies upon the velocity of bulk flow and its horizontal component.

CLC Number:

• TK124