Interface shape and wave velocities of air-water flows in a vertical duct

摘要

This paper describes the experimental investigation of an upward annular air-water flow in a duct with a 6.35 mm by 63.5 mm rectangular cross section. The test section was instrumented to study the shape of the interface and the interfacial wavevelocity. Flush-wire electrical conductivity probes were used to obtain local film thickness measurement with a spatial resolution of 200μm or better and a temporal resolution greater than 2 kHz. The probe design and a statistical calibration method arediscussed. Two flush-wire probes which allow the determination of wave propagation velocities have been implemented. Pressure drop in the channel was measured to provide a measure of averaged momentum transfer in the channel. A simple model for theprediction of interfacial wave velocities is presented, and it matches the data favorably.