A preliminary study of two-phase annular flow at microgravity: experimental data of film thickness

Film thickness time trace measurements were taken in normal (earth gravity) and microgravity (μ-g) conditions during parabolic flights operated by NASA Johnson Space Center in Houston, Texas. The measurements were taken using a parallel wire probe. Using the data, average film thickness, film minimum thickness, wave peak height, wave frequency and wave velocity were calculated over a wide range of liquid and gas mass velocities. The liquid mass velocity ranged from 49 to 318 kg/m2 s, and the gas mass velocity ranged from 2.3 to 25 kg/m2 s. While, based on average values of the film thickness, there were small differences between the 1-g and μ-g results, the wave base height and frequency were strongly affected by the reduction in gravity.