CHARACTERIZATION OF SUBREGIMES IN 2-PHASE SLUG FLOW

A new subdivision of the slug flow region, determined on the basis of different how features, is presented. The characteristic features of e ach subregime have been shown by diffusional analysis of experimental time series relative to intermittent flow. It is found that, at low va lues of the mixture velocity, V-m = j(L) + j(G), a subregime (elongate d bubble with dispersed bubble, EDB) with structural characteristics d ifferent from those usually attributed to slug flow (slug, SL) exists. It is demonstrated that the application of slug flow models to the wh ole slug flow region may lead to errors in the estimation of flow para meters, especially in large-diameter pipes (industrial application). A modification of the existing models for the flow variables (slug tran slational velocity, slug length and slug void fraction) is proposed in the light of the results obtained and confirmed against present and e xisting data. Copyright (C) 1996 Elsevier Science Ltd.