In this study, by applying the new computational model proposed by Bejan, laminar natural convection heat transfer from three horizontal attached cylinders has been studied numerically over the Rayleigh number range 10 ≤ Ra ≤ 106 and at the Prandtl number Pr=0.707 0. The comprehensive results consisting of streamlines, isothermal contours, and local and average Nusselt numbers are presented with different Rayleigh numbers. The obtained results show that a vortex is formed in the space between the adjacent two cylinders. The maximum local Nusselt number appears near θ=140°, and it increases with the Rayleigh number. Furthermore, this work accurately fits the equation dascribing the variation of average Nusselt number of the three cylinders with Rayleigh number. Hence the heat transfer coefficient of natural convection can be determined, and an accurate reference value is provided for industrial application.
SHI Hongyan
,
LIU Jie
,
LU Wenqiang
. Numerical simulation of laminar natural convection heat transfer from three horizontal attached cylinders[J]. Journal of University of Chinese Academy of Sciences, 2018
, 35(5)
: 595
-601
.
DOI: 10.7523/j.issn.2095-6134.2018.05.004
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