缩放管强化传热机理分析Mechanism of Heat Transfer Enhancement for Converging-diverging Tube
黄维军,邓先和,周水洪
HUANG Wei-jun,DENG Xian-he,ZHOU Shui-hong(South China University of Technology
摘要(Abstract):
应用数值模拟方法对光滑圆管与缩放管内的空气湍流对流传热在相同条件下进行了计算,对缩放管与光滑圆管内的对流传热系数、速度模量分布、径向速度分布、湍流强度的对比表明:缩放管内空气对流传热系数的提高,是近壁区域流体扰动增强产生了较大的流动径向速度与湍流强度的结果。表面传热系数、近壁区径向速度、近壁区湍流强度三者沿流向周期性变化的规律一致。缩放管强化传热的机理分析指出,强化气体传热的粗糙高度应位于流动过渡区。
The turbulent air flow and heat transfer in converging-diverging tube were numerically simulated with constant properties,periodically developed flow and uniform wall temperature considered,as well as for smooth tube under the same condition.The compare of heat transfer coefficient distribution,velocity magnitude distribution,radial velocity distribution and turbulent intensity distribution between converging-diverging tube and smooth tube was conducted.The Results showed that the augmentation of airflow heat transfer in converging-diverging tube was due to disturb to the near wall fluid,intensified radial velocity and turbulent intensity.The periodically variation of heat transfer coefficient along flow direction was in exactly accordance with that of radial velocity and turbulent intensity in near wall region.The optimum roughness height was stressed to be in flow buffer region to achieve better air flow hydraulic and thermal characteristics.
关键词(KeyWords):
数值模拟;对流传热系数;径向速度;湍流强度
numerical simulation;heat transfer coefficient;radial velocity;turbulent intensity
基金项目(Foundation): 国家重点基础研究发展规划项目(G2000026301)
作者(Author):
黄维军,邓先和,周水洪
HUANG Wei-jun,DENG Xian-he,ZHOU Shui-hong(South China University of Technology
参考文献(References):
- [1]Bergles Arthur E.Heat transfer enhancement———the ma-turing of second-generation heat transfer technology[J].Heat Transfer Engineering,1997,18(1):47-55.
- [2]Holman J P.Heat Transfer(Ninth edition)[M].Singa-pore:McGraw-Hill Higher Education,2002.
- [3]孟继安,陈泽敬,李志信,等.交叉缩放椭圆管换热与流阻实验研究及分析[J].工程热物理学报,2004,25(5):813-815.
- [4]张亚君,李军,邓先和,等.几种强化传热管的流阻和传热性能[J].石油化工设备,2004,33(5):5-7.
- [5]Pedro G.Vicente,Alberto Garcia,Antonia Viedma.Heattransfer and pressure drop for low Reynolds turbulent flowin helically dimpled tubes[J].International Journal ofHeat and Mass Transfer,2002,45:543-553.
- [6]Webb D L.,Webb R L.Forced convection heat transferin helically rib-roughened tubes[J].International Journalof Heat and Mass Transfer,1980,23:1127-1136.
- [7]邓先和,叶树滋.新型换热器在硫酸转换系统中的应用[J].硫酸工业,1996,(10):19-23.
- [8]徐光泽.金昌冶炼厂硫酸新系统建设方案探讨[J].硫酸工业,2004,(3):23-27.
- [9]张建文,张政.螺旋内翅片管内充分发展流体流动与传热的数值分析[J].高校化学工程学报,1999,13(2):114-120.
- [10]马良栋,孙德兴,张吉礼.内环肋管道中湍流流动与换热的数值模拟[J].哈尔滨工业大学学报,2004,136(14):438-512.
- [11]崔海亭,赵欣.螺旋横纹管管内紊流流动与换热数值研究[J].河北科技大学学报,2002,23(4):86-89.
- [12]Arman B,Rabas T.Two-Layer-Model predictions ofheat transfer inside enhanced tubes[J].Numerical HeatTransfer,Part A,1994,25:721-741.
- [13]陶文铨.数值传热学(第二版)[M].西安:西安交通大学出版社,2001.
- [14]Rabas T J.Selection of the energy-efficient enhancementgeometry for single-phase turbulent flow inside tubes[J].National heat transfer,1989,108:193-204.
- [15]Webb R L,Eckert E R G.Application of Rough Sur-faces to Heat Exchanger Design[J].Int.J.Heat MassTransfer,1972,15:1647-1658.
- [16]孟继安,陈泽敬,李志信,等.交叉缩放椭圆管换热与流阻实验研究及分析[J].工程热物理学报,2004,25(5):813-815.
- [17]吕静,王中铮.利用纵向涡发生元强化传热[J].暖通空调,2001,31(5):47-48.
- [18]周勇,张永恒,王良璧.涡产生器翼高对管板式换热器传热特性的影响[J].兰州铁道学院学报,2001,20(4):34-37.