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ISSN Online: 2379-1748

ISBN Flash Drive: 978-1-56700-431-1

ISBN Online: 978-1-56700-430-4

First Thermal and Fluids Engineering Summer Conference
August, 9-12, 2015 , New York City, USA


Get access (open in a dialog) pages 585-596
DOI: 10.1615/TFESC1.cmd.012545


Turbulent flow of water driven by a moving wall in the presence of air in a rectangular enclosure is investigated. Reynolds number based on the speed and length of the moving wall is Re = 578,302 for water and Re = 31,746 for air. Two enclosure aspect ratios of one (cube) and infinity are considered. The flow reveals complex and multi-scale structures with an unsteady and evolving nature. The larger structure of the flow is resolved using Large Eddy Simulation, while the sub-grid scales are captured by the dynamic k-equation eddy-viscosity model. The flow special features include the presence of a smooth water layer along the moving wall, an unstable and tumultuous flow along the stationary walls, impingement upon water-air interface, and entrainment of air into the pool of water and bubble formation. This investigation reveals mild liquid ripples along the moving wall, a more complex wavy flow along the stationary top wall leading to the formation and ejection of small droplets. It is further observed that the vigorous motion of air bubbles with numerous bubble coalescences create a complex flow field that has profound effects on parameters such as the transient driving force of the moving wall of the enclosure. In addition to flow features, this paper presents the time history of the driving power for the moving wall and the vorticity fields.