DROP DEPOSITION AND HEAT TRANSFER IN TWO-COMPONENT DISPERSED FLOW.

摘要

Theoretical and experimental studies have been carried out to further investigate the turbulent deposition of particles from two-phase droplet flow onto the smooth wall of a vertical tube. The work of Ganic & Mastanaiah (1981) for the Stokes regime has been extended by this study to include the Oseen regime (Re(,p) (LESSTHEQ) 5).;Theoretical and experimental studies have been carried out to study the heat transfer in two-component, two-phase flow, using an electrically heated 12.95 mm I.D. vertical stainless steel tube of 889 mm. The theoretical model takes into consideration the non-evaporating fraction of the droplets which are deposited on the wall, and all the possibilities of having a liquid film on the wall, especially when the wall temperature is less than the saturation temperature, are considered. A comparison between the proposed model and the available experimental data has been done. Finally, an empirical correlation is developed to predict the heat transfer coefficient in two-phase flow, knowing the initial conditions. A similar equation was developed to predict the local wall temperature.;The proposed theory satisfactorily describes the existing data, as well as the new data taken for air-water droplet flow passing through a 12.7 mm diameter stainless steel tube at Re = 27000, 36000, 43000 and 55000.