【摘要】 本文在总结大量实验资料基础上提出了对带横肋和圆形绕丝的环形通道中的换热和阻力计算公式,分析了粗糙元参数和流体Pr数对粗糙通道热力性能的影响。文中还分析了肋加槽型复合粗糙面的优良性能,提出相应的计算公式。更多还原

【Abstract】 Heat transfer and friction correlations are provided for turbulent flow in concentric annuli having different ribroughness. In order to clearly predict the influence of roughness parameter on heat transfer coefficient, the experimental data obtained by previous workers are correlated in the following formand the friction correlation isThe correlations were verified experimentally covering the range: 0.009≤h/de≤0.05, 7.2≤,s/h≤21, Pr=0.7-11 Re=8×103-1.2×106, rib geometries were square, triangular and circular.In this study excellent results for compound roughened surface with both ribs and grooves were also obtained. Heat transfer rate through this type of roughened surface is obviously higher than pure ribbed surface, but friction factor is only slightly larger.更多还原