...
  • 主题
高级搜索  >
历史搜索 清空历史
首页> 外文期刊>Journal of Heat Transfer >Laminar Boundary Layer Development Around a Circular Cylinder: Fluid Flow and Heat-Mass Transfer Characteristics
【24h】

Laminar Boundary Layer Development Around a Circular Cylinder: Fluid Flow and Heat-Mass Transfer Characteristics

机译：圆柱周围的层流边界层发展：流体流动和热质传递特性

获取原文
获取原文并翻译 | 示例
           
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

This paper presents a comprehensive computational work on the hydrodynamic, thermal, and mass transfer characteristics of a circular cylinder, subjected to confined flow at the cylinder Reynolds number of Re_d= 40. As the two-dimensional, steady and incompressible momentum and energy equations are solved using ANSYS-CFX (version 11.0), the moisture distributions are computed by a new alternating direction implicit method based software. The significant results, highlighting the influence of blockage (β = 0.200-0.800) on the flow and heat transfer mechanism and clarifying the combined roles of fi and moisture diffusivity (D = 1 ×10~(-8)-1 ×10~(-5) m~2/s) on the mass transfer behavior, are obtained for practical applications. It is shown that the blockage augments the friction coefficients (C_f) and Nusselt numbers (Nu) on the complete cylinder surface, where the average Nu are evaluated as Nu_(aue) =3.66, 4.05, 4.97, and 6.51 for β =0.200, 0.333, 0.571, and 0.800. Moreover, the blockage shifts separation (θ_s) and maximum C_f locations (θ_(C_f-max)) downstream to the positions of θ_s= 54.10, 50.20, 41.98, and 37.30 deg and θ_(C_f-max))=51.5, 53.4, 74.9, and 85.4 deg. The highest blockage of β = 0.800 encourages the downstream backward velocity values, which as a consequence disturbs the boundary layer and weakens the fluid-solid contact. The center and average moisture contents differ significantly at the beginning of drying process, but in the last 5% of the drying period they vary only by 1.6%. Additionally, higher blockage augments mass transfer coefficients (h_m) on the overall cylinder surface; however, the growing rate of back face mass transfer coefficients (h_(m-bf)) is dominant to that of the front face values (h_(m-ff)), with the interpreting ratios of h_(m-bf)/h_m=0.50 and 0.57 and h_(m-ff)/h_m = 1.50 and 1.43 for β = 0.200 and 0.800.
机译：本文介绍了圆柱的水动力，热和传质特性的综合计算工作，该圆柱在Re_d = 40的圆柱的雷诺数下受约束流。由于二维，稳定和不可压缩的动量和能量方程为使用ANSYS-CFX（版本11.0）求解时，水分分布是通过基于新的交替方向隐式方法的软件来计算的。结果显着，突出了阻塞（β= 0.200-0.800）对流动和传热机理的影响，并阐明了fi和湿气扩散率的组合作用（D = 1×10〜（-8）-1×10〜（对于实际应用，获得了-5）m〜2 / s）的传质性能。结果表明，堵塞会增加整个气缸表面的摩擦系数（C_f）和努塞尔特数（Nu），其中对于β= 0.200，平均Nu分别为Nu_（aue）= 3.66、4.05、4.97和6.51， 0.333、0.571和0.800。此外，障碍物将间距（θ_s）和最大C_f位置（θ_（C_f-max））向下游移动到θ_s= 54.10、50.20、41.98和37.30度，θ_（C_f-max））= 51.5、53.4， 74.9度和85.4度β= 0.800的最大阻塞会促进下游向后速度值，因此会干扰边界层并削弱流固接触。在干燥过程开始时，中心水分含量和平均水分含量显着不同，但在干燥期的最后5％内，它们的变化仅为1.6％。另外，较高的阻塞会增加整个气缸表面的传质系数（h_m）；但是，后表面传质系数（h_（m-bf））的增长率主要是前表面值（h_（m-ff））的增长率，解释比率为h_（m-bf）/ h_m对于β= 0.200和0.800，= 0.50和0.57，h_（m-ff）/ h_m = 1.50和1.43。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号