Experimental Investigation of Air–Water Flow Properties of Offset Aerators
Publication: Journal of Hydraulic Engineering
Volume 144, Issue 2
Abstract
Although chute aerators have been investigated experimentally by many researchers, only a few studies have been conducted on the comprehensive air–water flow properties of the lower jet downstream chute aerators. In this study, after eliminating the upper aeration of the jet, a complete characterization was recorded and presented for the distributions of air concentration, air–water velocity, and bubble frequency. Based on these extensive tests, a comprehensive equation to compute the air concentration distributions of each zone was presented. The velocity distribution had a shape similar to that of shear air–water flows; however, the quantitative parameters differ in each zone. In the cavity zone, the position of the maximum air bubble frequency was largely within a region of relatively high air concentration and gradually approached an equal air concentration of 0.50. The location of the maximum air bubble frequency was approximately the same as that of the section maximum air concentration at a section in the impact zone, but lower than that in the equilibrium zone. Self-similar relationships between the air concentration and bubble frequency were proposed for each zone.
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Acknowledgments
This work was supported by the National Key Research and Development Program (Grant No. 2016YFC0401707) and the National Natural Science Foundation of China (Grant Nos. 51479129 and 51679157).
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Published In
Journal of Hydraulic Engineering
Volume 144 • Issue 2 • February 2018
Copyright
©2017 American Society of Civil Engineers.
History
Received: Feb 7, 2017
Accepted: Jul 3, 2017
Published online: Nov 16, 2017
Published in print: Feb 1, 2018
Discussion open until: Apr 16, 2018
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