Slug flow in a vertical narrow rectangular channel - Laminar and turbulent regimes in the main flow and turbulent regime in the wake region of the Taylor bubble

Using a high-speed video-camera system, the hydrodynamics of gas-liquid two-phase slug flow in a vertical narrow rectangular channel with the cross section of 2.2 mm × 43 mm is investigated for laminar and turbulent regimes in the main flow and turbulent regime in the wake region of the Taylor bubble. The Taylor bubble velocity is the function of the liquid slug length ahead of it, and the interaction of Taylor bubbles for turbulent flow in main flow is weaker than that for laminar flow. Thus, two correlations are proposed for laminar and turbulent flows, respectively. The distributions of Taylor bubble velocity, lengths of liquid slug and Taylor bubble are all positively skewed. The lengths of Taylor bubble and the liquid slug decrease with the liquid flow rate. The Taylor bubble length increases with the gas flow rate, whereas the influence of the gas flow rate on the liquid slug length is insignificant.