Mechanism of natural convection around heated microwire at low Rayleigh number

被引:0
作者
Dai, Chuanshan [1 ]
Wang, Jue [1 ]
机构
[1] Key Laboratory of Efficient Utilization of Low and Medium Grade Energy, School of Mechanical Engineering, Tianjin University, Tianjin
来源
Huagong Xuebao/CIESC Journal | 2015年 / 66卷 / 07期
关键词
Low Rayleigh number; Microscale; Natural convection; Scale effect; Vibrating heated wire;
D O I
10.11949/j.issn.0438-1157.20150010
中图分类号
学科分类号
摘要
The mechanism of natural convection around horizontal and vertical heated microwires in silicon oil is studied by using the wire itself for temperature measurement. The comparison between present measured Nusselt numbers and those in literature shows that the present data agreed better with those of Tsubouchi than those of Fand. The horizontal microwire presents a larger Nu than the vertical one at low Rayleigh number. However, all of these experimental Nu are much larger than the numerically simulated values. In order to give a theoretical explanation on this phenomenon, heated microwire with weak vibration was used in the numerical simulations. The simulated Nu shows a perfect match with the measured data and are in agreement with the correlation of Tsubouchi with a deviation less than 5%. Therefore, an enhanced heat transfer mode due to weak wire vibration is proposed, to fill the gap between simulated and experimental results. ©, 2015, Chemical Industry Press. All right reserved.
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页码:2420 / 2425
页数:5
相关论文
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