J.C.Umavathi, LIU I-chung, M.Shekar. Unsteady Mixed Convective Heat Transfer of Two Immiscible Fluids Confined Between a Long Vertical Wavy Wall and a Parallel Flat Wall[J]. Applied Mathematics and Mechanics, 2012, 33(7): 877-895. doi: 10.3879/j.issn.1000-0887.2012.07.008
 Citation: J.C.Umavathi, LIU I-chung, M.Shekar. Unsteady Mixed Convective Heat Transfer of Two Immiscible Fluids Confined Between a Long Vertical Wavy Wall and a Parallel Flat Wall[J]. Applied Mathematics and Mechanics, 2012, 33(7): 877-895.

# Unsteady Mixed Convective Heat Transfer of Two Immiscible Fluids Confined Between a Long Vertical Wavy Wall and a Parallel Flat Wall

##### doi: 10.3879/j.issn.1000-0887.2012.07.008
• Rev Recd Date: 2011-12-28
• Publish Date: 2012-07-15
• 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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