Dispersed Two-Phase Flows, its Experimental Investigation and Numerical Prediction

Abstract

The measurement of particle velocities, size distribution and concentration has become of considerable interest to environmental control and protection agencies as well as to engineers and scientists working on pollution problems. Furthermore, there are many flows in natural and industrial environment in which suspended particles influence or even dominate heat and mass transfer processes. Detailed studies of these transfer processes require suitable measuring techniques to provide information on particle velocity, size distribution and concentration and on variations of these quantities in time and space. Hence, the occurence of two-phase or multiphase flows in different fields of engineering is large and their properties differ due to the wide variety of phase combinations and due to the large number of possible flow regimes. In recent years considerable progress has been made understanding the physics of some of these regimes of dispersed two-phase flows. This understanding was achieved by means of detailed experimental investigations that will shortly be summarized in section 2 of this paper. The results of these studies entered two-phase flow modelling refining numerical prediction procedures for dispersed two-phase flows.These are looked at in section 3.