Abstract

The present work reports simultaneous bubble size and gas transfer measurements in a bubbly wake flow of a hydrofoil, designed to be similar to a hydroturbine blade. Bubble size was measured by a shadow imaging technique and found to have a Sauter mean diameter of 0.9 mm for a reference case. A lower gas flow rate, greater liquid velocities, and a larger angle of attack all resulted in an increased number of small size bubbles and a reduced weighted mean bubble size. Bubble-water gas transfer is measured by the disturbed equilibrium technique. The gas transfer model of Azbel (1981) is utilized to characterize the liquid film coefficient for gas transfer, with one scaling coefficient to reflect the fact that characteristic turbulent velocity is replaced by cross-sectional mean velocity. The coefficient was found to stay constant at a particular hydrofoil configuration while it varied within a narrow range of 0.52-0.60 for different gas/water flow conditions.

Details

Title
Gas transfer in a bubbly wake flow
Author
Karn, A 1 ; Gulliver, J S 2 ; Monson, G M 3 ; Ellis, C 4 ; Arndt, R E A 4 ; Hong, J 1 

 Saint Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN, USA; Department of Mechanical Engineering, University of Minnesota, Minneapolis, MN, USA 
 Saint Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN, USA; Department of Civil, Environmental and Geo Engineering, University of Minnesota, Minneapolis, MN, USA 
 Houston Engineering, Maple Grove, MN, USA 
 Saint Anthony Falls Laboratory, University of Minnesota, Minneapolis, MN, USA 
Publication year
2016
Publication date
May 2016
Publisher
IOP Publishing
ISSN
17551307
e-ISSN
17551315
Source type
Scholarly Journal
Language of publication
English
ProQuest document ID
2548462468
Copyright
© 2016. This work is published under http://creativecommons.org/licenses/by/3.0/ (the “License”). Notwithstanding the ProQuest Terms and Conditions, you may use this content in accordance with the terms of the License.