Study of gas-sheared liquid film in horizontal rectangular duct using high-speed LIF technique: Three-dimensional wavy structure and its relation to liquid entrainment

• Published in: International journal of multiphase flow Vol. 67; pp. 52 - 64
• Main Authors: Cherdantsev, Andrey V., Hann, David B., Azzopardi, Barry J.
• Format: Journal Article
• Language: English; Russian
• Published: Kidlington Elsevier Ltd 01.12.2014; Elsevier
• Subjects: Annular flow; Disturbance waves; Gas-sheared liquid film; Laser-induced fluorescence; Liquid entrainment; Ripples; Disturbance waves; Gas-sheared liquid film; Laser-induced fluorescence; Ripples; Liquid entrainment; Annular flow
• ISSN: 0301-9322; 1879-3533
• DOI: 10.1016/j.ijmultiphaseflow.2014.08.003

•Flow of horizontal gas-sheared film is studied using LIF technique.•Film thickness data are resolved in longitudinal and transverse coordinates and time.•The process of ripples generation is qualitatively the same in different conditions.•Three-dimensional structure of disturbance waves and fast ripples is studied.•Bag and ligament break-up events are related to the wavy structure of liquid film. The flow of a liquid film sheared by high velocity gas stream in a horizontal rectangular duct was investigated using a high-speed laser-induced fluorescence technique. Measurements of local film thickness were resolved in both longitudinal and transverse coordinates with high spatial and temporal resolution. It was found that the generation of fast and slow ripples by the disturbance waves was qualitatively the same as it was observed earlier in completely different conditions. The transverse size and curvature of the disturbance waves and ripples were measured. A relationship between the three-dimensional structure of ripples on top of disturbance waves and the two mechanisms of liquid entrainment, known as ‘bag break-up’ and ‘ligament break-up’, is proposed.