Dilution of Multiple Nonbuoyant Circular Jets in Crossflows
Publication: Journal of Environmental Engineering
Volume 124, Issue 1
Abstract
This paper presents the results of a laboratory study on the mixing of circular nonbuoyant multiple jets discharged into relatively deep river-like crossflows. Experiments were performed for the velocity ratio α varying from 3.5 to 10 where α is the ratio of the velocity of the jet to that of the crossflow. Three and five ports were used and the spacing S between the ports was varied from 8d to 16d where d is the diameter of the nozzle. The concentration measurements were carried out for a maximum relative distance of x/d= 160 where x is the distance downstream of the diffuser. The concentration profiles in the vertical as well as the lateral directions in the planes of maximum concentration were found to be similar. The minimum dilution at any section, defined as the inverse ratio of the maximum concentration at that section to that at the ports, reached a value of 80 in the mixing region. The minimum dilution decreased as α increased. Equations have been developed to describe the growth of the width and thickness of these jets. These results are believed to be useful in the design of outfalls in rivers.
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Information
Published In
Journal of Environmental Engineering
Volume 124 • Issue 1 • January 1998
Pages: 51 - 58
Copyright
Copyright © 1998 American Society of Civil Engineers.
History
Published online: Jan 1, 1998
Published in print: Jan 1998
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