The Friction and Heat Transmission Coefficients of Rough Pipes
The Friction and Heat Transmission Coefficients of Rough Pipes
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DOI：
10.1243/pime_proc_1941_145_026_02
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发表时间：
1941-06
期刊：
影响因子：
--
通讯作者：
W. F. Cope
中科院分区：
文献类型：
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作者：
W. F. Cope
在以前的一篇论文（科普，1937）中，曾对一系列不同截面形状的光滑管的传热系数和摩擦系数同时进行了测量。这些结果形成了对热传递问题进行全面研究的第一部分。本文是第二部分，叙述了粗糙管的试验结果。测试了三个管道，它们的内表面通过特殊的滚花工艺人工粗糙化，该工艺产生了一系列几何形状相似但绝对尺寸不同的金字塔。粗糙度比（管道半径/金字塔高度）约为8/1、15/1和45/1。所用的装置与以前试验中所用的装置基本相同;工作流体为水，雷诺数范围为2，000至60，000。结果表明，在充分湍流条件下，粗糙度对传热系数的影响很小。
In a previous paper (Cope 1937)† an account was given of the simultaneous measurement of the heat transmission and friction coefficients of a series of smooth pipes of various shapes of cross-section. The results formed the first section of a comprehensive research into the problem of heat transmission. The present paper, which describes the results of tests on rough pipes, forms the second section. Three pipes were tested, their internal surfaces being artificially roughened by a special knurling process which produced a series of pyramids geometrically similar in form but varying in absolute size from pipe to pipe. The roughness ratios (radius of pipe/height of pyramid) were approximately 8/1, 15/1, and 45/1. The apparatus used was basically the same as that used in the previous tests; the working fluid was water, and the Reynolds number ranged from 2,000 to 60,000. The results indicate that when fully turbulent conditions are established the roughness has very little effect on the heat transmission coe...