Difference between film and drop wise condenation?

Answer 1

Filmwise condensation occurs on 'wettable' materials as a formation of film on the surface,While dropwise condensation occurs on 'nonwettable' material as spherical drops form on the surface.These drops adhere together to become larger as condensation proceeds. Usually the heat transfer coefficient in dropwise is 5-8 times larger than that of filmwise condensation.Filmwise condensation is more common than the Dropwise condensation.

Answer 2

Film condensation occurs when a continuous film of condensed liquid forms on a surface, while dropwise condensation occurs when individual droplets of condensed liquid form and coalesce on a surface. Dropwise condensation is more efficient than film condensation in terms of heat transfer, but it is more difficult to achieve and maintain in practice.