HEAT TRANSFER CHARACTERISTICS AND DYNAMIC BEHAVIOR OF SATURATED DROPLETS IMPINGING ON A HEATED VERTICAL SURFACE.

Abstract

Experiments were made with droplets impinging on a heated vertical surface in a range of low droplet Weber numbers mostly from 10 to 200. Data of the heat transfer effectiveness of individual droplets measured by means of a transient technique are presented. When the wall superheat is higher than a certain value, the droplet rebounds away from the surface with a very low heat transfer effectiveness. Behavior of the droplets on the surface was observed and heat transfer characteristics during the residence time of a droplet on the high temperature surface were examined based on the time-dependent variation of the wall temperature measured near the surface.