The Unsteady Behavior of the Natural Convection Heat Transfer in a Square Enclosure by 90° Rotate

Authors

Yazd university

Abstract

The natural convection heat transfer in a square enclosure depends on the geometry of the enclosure, the amount and the type of heating and cooling on the hot and cold walls, the fluid proprieties and the inclination angle of the enclosure. In this paper, the natural convection in a square enclosure with two hot and cold vertical walls and two adiabatic horizontal walls is investigated. This vertical enclosure by rotating 90° changes into a horizontal enclosure. The aim of this study is to investigate the time dependent behavior of the flow and the heat transfer through it affected by the inclination angle. The lattice Boltzmann method for numerical simulation of the fluid flow and the heat transfer is used. The problem is solved by five values of rotation times for Rayleigh number 105. Streamlines, temperature distribution and the amount of heat transfer in every time obtained. The results show that by the fast rotation major changes in the temperature distribution and the heat transfer occurs after the stopping of rotation. But in the slow rotation the amount of heat transfer is very close to the steady state in any time at the same situation.

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References

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Journal of Solid and Fluid Mechanics
Volume 5, Issue 2 - Serial Number 2
July and August 2015
Pages 329-339

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