Film condensation on a finite-size horizontal wavy plate bounded by a homogenous porous layer

Steady filmwise condensation on a finite-size horizontal wavy plate which covers a homogeneous porous medium layer filled with a dry saturated vapor has been investigated by boundary layer approximations. The dimensionless average Nusselt number Nu¯ and dimensionless liquid film thickness on the wavy surface are evaluated as a function of seven parameters: Darcy number Da, Jacob number Ja, the wave number n, Prandtl number Pr, modified Rayleigh number Ra, suction parameter Sw and the wave amplitude α. It is shown that the condensation heat transfer coefficient can be enhanced by increasing the contact area of the condensate, which corresponds to increasing values of the wave number and amplitude of the wavy surface, and when suction exists at the condensate surface.