Unsteady Mixed Convective Heat Transfer of Two Immiscible Fluids Confined Between a Long Vertical Wavy Wall and a Parallel Flat Wall
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摘要: 分析粘性、不可压缩、互不相溶流体,在竖直的波状壁面和光滑的平面壁间,传热传质混合对流的组合效应.得到无量纲控制方程的摄动解:0阶的均值部分和1阶的摄动部分.将所得到的1阶量,用小波长摄动级数展开,出现按指数阶分类的方程组.得到了0阶和1阶的解析表达式及其整体解,通过数值计算,用图形表明流体流动的显著特征以及传热特性.界面上应用适当的匹配条件,使分离的解相匹配.还针对控制参数的不同变化,分析了剪应力和Nusselt数的变化.发现Grashof数、粘性比、宽度比和导电率,对平行于流动方向的速度是有利的,对垂直于流动方向速度的影响正相反.Abstract: An analysis on the combined effects of thermal and mass convection of viscous incompressible, immiscible fluids through a vertical wavy wall and a smooth flat wall was performed. The dimensionless governing equations were perturbed into: mean part (zeroth order) and a perturbed part (first order). The first order quantities were obtained by perturbation series expansion for short wavelength, in which terms of exponential order arise. Analytical expressions for the zeroth order, first order and the total solutions were obtained.The numerical computations were presented graphically to show salient features of the fluid flow and heat transfer characteristics. Separate solutions were matched at the interface by using suitable matching conditions. The shear stress and the Nusselt number were also analyzed for different variations of the governing parameters. It is observed that Grashof number, viscosity ratio, width ratio and conductivity ratio promote the velocity parallel to the flow direction. A reversal effect is observed for the velocity perpendicular to the flow direction.
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Key words:
- mixed convection /
- wavy wall /
- immiscible fluids /
- perturbation method
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