An analytical investigation into the Nusselt number and entropy generation rate of film condensation on a horizontal plate

This study investigates the heat transfer characteristics and entropy generation rate of a condensate film formed on a horizontal plate with suction at the wall. Applying the minimum mechanical energy principle, the dimensionless liquid film thickness along the plate is found to vary as a function of the Rayleigh number, the Jakob number, the Prandtl number and the suction parameter. The governing differential equation of the condensate thickness is solved numerically by using a finite-difference shooting method. Closed-form analytical expressions are derived for the Nusselt number and the dimensionless overall entropy generation number. When there is no suction at the wall, the results obtained from the analytical expression for the Nusselt number are found to be in good agreement with those presented in the literature.