Horizontal Slug Flow: A Comparison of Existing Theories

Abstract

Over the last twenty years a number of papers have appeared in literature concerning the transition to slug flow in horizontal two-phase flow. The theories proposed in these papers are described, and compared to each other and to results of experiments. It is found that most writers accept that the transition is due to Kelvin-Helmholtz instability of the waves, but if this is studied on the basis of wave motion equations, the transition is found to be dependent on wavelength which contradicts experimental data. A number of authors look at this instability by studying the Bernoulli equation, but this does not predict the wave height. Various approaches are taken by the authors to determine this quantity.