LAMINAR NATURAL CONVECTIVE HEAT-TRANSFER OVER 2 VERTICALLY SPACED ISOTHERMAL HORIZONTAL CYLINDERS

被引：11

作者：

PAYKOC, E

YUNCU, H

BEZZAZOGLU, M

机构：

[1] Mechanical Engineering Department, Middle East Technical University, Ankara

来源：

EXPERIMENTAL THERMAL AND FLUID SCIENCE | 1991年 / 4卷 / 03期

关键词：

NATURAL CONVECTION; LAMINAR FLOW; HORIZONTAL CYLINDERS; HOLOGRAPHIC INTERFEROMETRY;

D O I：

10.1016/0894-1777(91)90053-T

中图分类号：

O414.1 [热力学];

学科分类号：

摘要：

Theoretical and experimental studies of laminar natural convective heat transfer in air from a pair of heated horizontal cylinders placed one above the other in the vertical plane were carried out. In the theoretical study, a finite-difference scheme based on the integration of the governing equations over finite cells was used. The problem was experimentally investigated by the method of holographic interferometry. Interferograms were evaluated for a Rayleigh number range of 1.5 x 10(4) to 3.0 x 10(4). Temperature profiles around the two cylinders, radial and angular velocity distributions in the boundary layers of the cylinders, and variations of local heat transfer coefficients around both cylinders were obtained. The effect of separation distance between the cylinders on the heat transfer from the upper cylinder was considered. It was seen that the average Nusselt number of the upper cylinder increases and approaches that of the lower cylinder as the separation distance is increased from 2 to 2.5 times the cylinder diameter. Theoretical predictions are compared with experimental results, and agreement is obtained within at most 25%.

引用

页码：362 / 368

页数：7

共 11 条

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