Multi-scale cross entropy analysis for inclined oil-water two-phase countercurrent flow patterns

The flow of an oil-water two-phase fluid in an inclined pipe exhibits fundamentally different behaviors to that of a vertical two-phase flow, especially the flow commonly presents complex countercurrent flow structure due to the influence of gravity. The understanding of inclined oil-water flow is of important significance for flow measurement and production optimization. We using multi-scale cross entropy (MSCE) analysis investigate the nonlinear dynamics of inclined water-dominated oil-water two-phase flow patterns which are Dispersion oil-in-water-Pseudoslugs (D O/W PS), Dispersion oil-in-water-Countercurrent (D O/W CT) and Transitional Flow (TF). We find that the rate of low-scale cross entropy can effectively identify flow patterns, and the high-scale cross entropy can represent their long-range dynamics. The research results show that the multi-scale cross entropy analysis can be a helpful tool for revealing nonlinear dynamics of inclined oil-water two-phase flow in terms of microscopic and macroscopic views. (C) 2011 Elsevier Ltd. All rights reserved.