• CN:11-2187/TH
  • ISSN:0577-6686

机械工程学报 ›› 2015, Vol. 51 ›› Issue (24): 168-176.doi: 10.3901/JME.2015.24.168

• 交叉前沿 • 上一篇    下一篇

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湍流边界层内钝体扰流的流动与传热特性

汪健生,  王晓,  朱强,  赵云俭   

  1. 天津大学中低温热能高效利用教育部重点实验室  天津  300072
  • 收稿日期:2014-12-14 修回日期:2015-09-25 出版日期:2015-12-15 发布日期:2015-12-15
  • 通讯作者: 朱强,男,1968年出生。主要研究方向为强化传热与动力循环技术。 E-mail:zq6868@tju.edu.cn
  • 作者简介:汪健生,男,1964年出生,博士,副教授。主要研究方向为流动控制与强化传热。 E-mail:jsw@tju.edu.cn

Flow and Heat Transfer Characteristics of Flow Past the Bluff Body in Turbulent Boundary Layer

WANG Jiansheng,  WANG Xiao,  ZHU Qiang,  ZHAO Yunjian   

  1. Key Laboratory of Medium-Low Temperature Thermal Energy Efficient Utilization of Ministry of Education, Tianjin University, Tianjin 300072
  • Received:2014-12-14 Revised:2015-09-25 Online:2015-12-15 Published:2015-12-15

摘要: 应用大涡模拟方法对小尺度开缝圆柱涡流发生器强化传热和流动减阻的机理进行研究。水平开缝圆柱置于充分发展湍流边界层内,分析不同间隙比对开缝圆柱尾流、湍流边界层拟序结构以及槽道底面流动与换热特性的影响。为验证所采用数值方法的准确性与可靠性,将矩形空槽道的计算结果与前人直接数值模拟结果及与采用相关准则关系式所得结果进行对比。计算结果表明:湍流边界层内钝体扰流的尾迹流与壁面边界层的相互作用能够显著提高槽道的换热性能。与未开缝的基准圆柱相比,间隙比小于2.0时,开缝圆柱通道的整体热性能较好;间隙比为2.0时,其综合性能系数最大;间隙比大于2.0时,整体热性能较差。与矩形空槽道相比,最大努塞尔数可提高17.45%,最小摩擦因数可减小4.94%。

关键词: 大涡模拟, 基准圆柱, 间隙比, 开缝圆柱, 强化传热

Abstract: The mechanism of heat transfer enhancement and flow drag reduction of small scale circular cylinder vortex generator with a slit is numerically investigated by large eddy simulation. The circular cylinder with a horizontal slit is located in the fully developed turbulent boundary layer. The influence of gap ratios on the circular cylinder wake, the coherent structure of turbulent boundary layer, flow and heat transfer characteristics of the channel bottom wall are probed. To validate the accuracy and reliability of the present numerical method, the results of the rectangular empty channel with present numerical method are compared with the results by direct numerical simulation and empirical correlation equation. The results show that the interaction between the wake flow of bluff body and the wall boundary layer can enhance prominently the overall thermal performance of the channel flow. Compared with the reference cylinder, the overall thermal performance is better when the gap ratio is less than 2.0, the synthetic coefficient reaches maximum when the gap ratio is 2.0, and the thermal performance is lower when the gap ratio is more than 2.0. Compared with the rectangular empty channel, the maximum Nusselt can be increased by 17.45%, the minimum frication coefficient can be decreased by 4.94%.

Key words: cylinder with slit, gap ratio, heat transfer enhancement, large eddy simulation, reference cylinder