Eventos Anais de eventos
ENCIT 2016
16th Brazilian Congress of Thermal Sciences and Engineering
CHARACTERIZATION OF BUBBLE PLUMES IN UNSTEADY CROSS FLOW
Submission Author:
Phillype de Lima Massari , RJ
Co-Authors:
Igor Braga de Paula, Maria Helena Farias
Presenter: Phillype de Lima Massari
doi://10.26678/ABCM.ENCIT2016.CIT2016-0512
Abstract
This paper presents an experimental investigation of the flow field induced by the interaction between a bubble plume and an oscillating cross flow. Similar flow conditions can be found in artificial aeration processes used for mitigation of pollution contamination in rivers and submarine outfalls in coastal areas. The mixing zones is highly dependent of the flow field near the plume. In the present work, controlled surface waves were introduced to generate oscillations in streamwise and wall normal components of the cross flow. The waves were excited with a moving paddle and shallow water conditions were selected for the investigation. Air was injected in the bottom wall of the water channel to form the bubble plume. Stereo Particle Image Velocimetry (SPIV) techniques were employed to measure the velocity flow field. Prior to velocity estimation, images were pre-processed using Matlab routines in order to distinguish tracer particles from air bubbles and to create a dynamic mask for the PIV images. Thus, the velocity vector field was estimated using standard PIV algorithms. In addition, properties of the bubbles, such as size and velocity, were also estimated from the acquired images. Finally, the interaction between the bubble plume with the unsteady cross flow was analyzed. Preliminary results suggest an influence of the wave amplitude on the dispersion of the plume.
Keywords
Air bubble plumes, Surface Waves, Unsteady Cross Flow, PIV, Experimental Study, Air bubble plumes, Surface Waves, Unsteady Cross Flow, PIV, Experimental Study, Air bubble plumes, Surface Waves, Unsteady Cross Flow, PIV, Experimental Study, Air bubble plumes, Surface Waves, Unsteady Cross Flow, PIV, Experimental Study
