Filmwise condensation

From Thermal-FluidsPedia

1 Regimes of Filmwise Condensation
2 Governing Equations for Laminar Film Condensation of a Binary Vapor Mixture
3 Filmwise Condensation in a Stagnant Pure Vapor Reservoir
4 Effects of Vapor Motion on Film Condensation
5 Turbulent Film Condensation
6 Other Filmwise Condensation Configurations
7 Film Condensation on Cylinders and Spheres
8 Flooding or Entrainment Limit
9 Effects of Noncondensable Gas on Film Condensation

Regimes of Filmwise Condensation

Filmwise condensation on a vertical surface occurs when the liquid phase fully wets the surface, whereas in dropwise condensation the liquid incompletely wets the solid surface. The condensation process begins with vapor condensing directly on the wall surface. However, in contrast with dropwise condensation, after the wall is initially wetted it remains covered by a thin film of condensate. After that point, condensation occurs only at the liquid-vapor interface.

See Main Article Regimes of Filmwise Condensation

Governing Equations for Laminar Film Condensation of a Binary Vapor Mixture

Knowledge of binary vapors is of the utmost practical importance, because pure vapor is rarely present in everyday life or in industrial applications. Consider the steady laminar film condensation of a binary vapor on a smooth, vertical, cooled wall. The bulk vapor mixture flows downwards and parallels the vapor boundary layer and condensate film flows, which are also flowing downwards due to the effects of gravity. For condensation of a binary vapor near a vertical plate, x is the distance measured along the flat plate starting from the leading edge and y is the normal distance from the plate.

See Main Article Governing Equations for Laminar Film Condensation of a Binary Vapor Mixture