Deterministic chaos analysis of pressure fluctuations in a horizontal pipe at intermittent flow regime

Different methods of analysis of chaotic time series of the wall pressure fluctuations were applied to characterize the intermittent flow patterns in a horizontal pipe. A weak sign of deterministic chaos was diagnosed within a transition from plug flow to slug flow. At higher superficial gas velocities, the amplitude modulation of the pressure pulses in the slug flow regime indicated a significant degree of correlation between the subsequent slugs. The transition to annular flow was found to occur via the gas blow through the shortest and most aerated slugs. The resulting transition patterns displayed the intermittency route to chaos.