Sweep-out Flow of Film Condensation on Vertical Plates with Horizontal Grooves

We have investigated fluid flow characteristics of filmwise condensation on vertical plates with horizontal grooves. The condensation fluid stays at the edge of the grooves due to the surface tension. The fluid starts to move, however, when the balance between the surface tension and the fluid's own weight are broken. It is found that the fluid flows downward periodically from the top part of the plate as a group. In addition, we have obtained the relation between the frequencies of the periodic flow and the degree of subcooling for two different pitches of the grooves.