Interfacial structure of air-water two-phase flow in a relatively large pipe

Miniaturized four-sensor conductivity probes are used to study flow structure development in air-water bubbly flow, cap-bubbly flow, and transition to slug flow. The measurements are performed at three different elevations in a vertical round pipe with an inner diameter of 101.6 mm. The time-averaged local void fraction, interfacial velocity, and bubble number frequency are measured by the conductivity probes. Also, the interfacial area concentration and averaged bubble Sauter mean diameter are obtained. A detailed representation of the flow structure is revealed by investigating the acquired data. Furthermore, comparisons of the data at three elevations demonstrate the development of the interfacial structure along the flow direction due to bubble interactions and hydrodynamic effects. This may provide the community with a better knowledge about two-phase flow in a relatively large pipe. In addition, these data can also serve as an experimental database for investigation of the interfacial area transport in large-pipe two-phase flow.