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An experimental investigation of microbubble generation in confined turbulent jet
conference contribution
posted on 2023-05-23, 05:08 authored by Paul BrandnerPaul Brandner, Wright, G, Bryce PearceBryce Pearce, Goldsworthy, L, Walker, GJMicrobubbles generated from the expansion of water supersaturated with dissolved air through a sharp edged orifice are investigated using shadowgraphy. Demineralised water saturated to an equilibrium concentration corresponding to 5 atmospheres is expanded through a 0.5 mm diameter x 0.3 mm thick orifice plate into a 1.2 mm diameter tube at atmospheric pressure. Cavitation occurrence in the small-scale turbulent structures combined with gaseous diffusion promotes the formation of microbubbles. The length affects bubble coalescence and hence the number and size of bubbles ejected. To enable measurements of bubble size and volumetric concentration the ejected bubble plume is dispersed in a co-flowing stream of fine-scale turbulence to achieve a homogeneous distribution in a transparent duct though which shadowgraphy measurements can be made. The buble shadows are created using diffused laser backlighting viewed with a CCD camera via a long range microscope.
History
Publication title
Proceedings of the 17th Australasian Fluid Mechanics ConferenceEditors
GD Mallinson and JE CaterISBN
978-0-86869-129-9Department/School
Australian Maritime CollegePublisher
Australian Fluid Mechanics SocietyPlace of publication
AustraliaEvent title
17th Australasian Fluid Mechanics ConferenceEvent Venue
AucklandDate of Event (Start Date)
2010-12-05Date of Event (End Date)
2010-12-09Rights statement
Copyright 2010 University of AucklandRepository Status
- Restricted