Abstract
The heat transfer coefficient decreases remarkably, when a liquid film disappears in the high quality region of evaporating tubes. It is desirable to hold the liquid film on the tube wall by some means. The purpose of this work is to investigate the behaviors of the liquid film and entrained droplets in a non-swirling and in a swirling downward annular-mist air-water flow, induced by a swirler inserted into the inlet of the test section (40 mm ID, 5 m long). This report presents the experimental results on the characteristics of the liquid film along the test section, such as the liquid film thickness, the velocity, and the wave length and the frequency of disturbance waves. Furthermore, the disturbance wave flowrate, the base liquid film flowrate, and the entrained droplet flowrate along the test section are obtained.
