Investigating the nonlinear dynamics of natural-circulation, boiling two-phase flows

The nonlinear dynamics of natural-circulation, boiling two-phase flows are investigated using a two-phase flow loop. Experiments have been carried out in the unstable operating region of the facility for various system pressures and for different frictions at the exit of the riser section. It appears that the boiling two-phase flow undergoes the well-known Feigenbaum scenario, the period-doubling route toward chaotic behavior. Evaluation of the recorded signals using nonlinear time series analysis methods indicates the occurrence of chaotic density-wave oscillations.