Near-Field Mixing Downstream of a Multiport Diffuser in a Shallow River
Publication: Journal of Environmental Engineering
Volume 137, Issue 4
Abstract
Near-field mixing downstream of a multiport diffuser in a wide shallow river was studied with a field dye test. Dye concentrations at different depths and lateral locations were measured. The near-field mixing was analyzed in four zones: the free jet zone, the jet surface-impingement zone, the merging zone, and the vertical mixing zone. Analytical models were proposed to derive the three-dimensional concentration field after the jets impinged the water surface. After the impingement, the dye concentration can be predicted well by treating the multiple jets as a simple mathematical summation of individual jets. The vertical mixing zone was dominated by the riverbed friction-induced turbulence, with little effect from the effluent momentum and buoyancy. The results of the field data were also used to validate the applicability of some existing models for multiport diffusers.
Get full access to this article
View all available purchase options and get full access to this article.
Acknowledgments
The writers would like to thank C. Krath, F. Bhuiyan, M. Spafford, Z. Pan, N. Hall, K. Sharma, J. Cai, and A. Camino for their help with the field work; P. Fedun for his support in the laboratory; T. McKenna for providing the effluent and diffuser information; and B. Liu for helping with the River2D model. We also give our appreciation to Dr. N. Rajaratnam and Dr. F. Bhuiyan for their advice on this paper.
References
Adams, E. E. (1982). “Dilution analysis for unidirectional diffusers.” J. Hydraul. Div., 108(HY3), 327–342.
Anthony, D. G., and Willmarth, W. W. (1992). “Turbulence measurements in a round jet beneath a free surface.” J. Fluid Mech., 243, 699–720.
CORMIX 5.0GT [Computer software]. MixZon, Portland, OR.
Cuthbertson, A. J. S., and Davies, P. A. (2008). “Deposition from particle-laden, round, turbulent, horizontal, buoyant jets in stationary and coflowing receiving fluids.” J. Hydraul. Eng., 134(4), 390–402.
Doneker, R. L., and Jirka, G. H. (1990). “Expert system for hydrodynamic mixing zone analysis of conventional and toxic submerged single port discharges (CORMIX1).” EPA/600/3-90/012, Environmental Research Laboratory of U.S. Environmental Protection Agency (USEPA), Athens, GA, 1–250.
Doneker, R. L., and Jirka, G. H. (2007). “CORMIX user manual—A hydrodynamic mixing zone model and decision support system for pollutant discharges into surface waters.” EPA-823-K-07-001, USEPA, Washington, DC, 206.
Fischer, H. B., List, E. J., Koh, R. C. Y., Imberger, J., and Brooks, N. H. (1979). Mixing in inland and coastal waters, Academic Press, San Diego.
Hodgson, J. E. (1991). “Turbulent jet discharges in rivers.” Ph.D. thesis, Dept. of Civil Engineering, Univ. of Alberta, Edmonton, AB, Canada.
Hodgson, J. E., Moawad, A. K., and Rajaratnam, N. (1999). “Concentration field of multiple circular turbulent jets.” J. Hydraul. Res., 37(2), 249–256.
Hodgson, J. E., and Rajaratnam, N. (1992). “An experimental study of jet dilution in crossflows.” Can. J. Civ. Eng., 19(5), 733–743.
Huang, H., Fergen, R. E., Rroni, J. R., and Tsai, J. J. (1996). “Probabilistic analysis of ocean outfall mixing zones.” J. Environ. Eng., 122(5), 359–367.
Jirka, G. H. (2004). “Integral model for turbulent buoyant jets in unbounded stratified flow—Part I: Single round jet.” Environ. Fluid Mech., 4(1), 1–56.
Jirka, G. H., and Harleman, D. R. F. (1973). “The mechanics of submerged multiport diffuser for buoyant discharges in shallow water.” R. M. Parsons Laboratory Rep., Massachusetts Institute of Technology, Boston, MA.
Kikkert, G. A., Davidson, M. J., and Nokes, R. I. (2009). “A jet at an oblique angle to a cross-flow.” J. Hydro-environ. Res., 3(2), 69–76.
Kim, D. G., and Seo, I. W. (2000). “Modeling the mixing of heated water discharged from a submerged multiport diffuser.” J. Hydraul. Res., 38(4), 259–269.
Knystautas, R. (1964). “The turbulent jet from a series of holes in line.” Aeronaut. Q., 15, 1–28.
Kuang, C. P., and Lee, J. H. W. (2006). “Stability and mixing of a vertical axisymmetric buoyant jet in shallow water.” Environ. Fluid Mech., 6(2), 153–180.
Lam, K. M., Lee, W. Y., Chan, C. H. C., and Lee, J. H. W. (2006). “Global behaviors of a round buoyant jet in a counterflow.” J. Hydraul. Eng., 132(6), 589–604.
Lee, J. H. W. (1985). “Comparison of two river diffuser models.” J. Hydraul. Eng., 111(7), 1069–1078.
Lee, J. H. W., and Chu, V. H. (2003). “Turbulent jets and plumes, a Lagrangian approach.” Kluwer Academic, Boston.
Lee, J. H. W., and Jirka, G. H. (1980). “Multiport diffuser as line source of momentum in shallow water.” Water Resour. Res., 16(4), 695–708.
Lima Neto, I. E., Zhu, D. Z., Rajaratnam, N., Yu, T., Spafford, M., and McEachern, P. (2007). “Dissolved oxygen downstream of an effluent outfall in an ice-covered river: natural and artificial aeration.” J. Environ. Eng., 133(11), 1051–1060.
Moawad, A. K., and Rajaratnam, N. (1998). “Dilution of multiple nonbuoyant circular jets in crossflows.” J. Environ. Eng., 124(1), 51–58.
Pani, B. S., Lee, J. H. W., and Lai, A. C. H. (2009). “Application of Reichardt’s hypothesis for multiple coflowing jets.” J. Hydro-environ. Res., 3(3), 121–128.
Parr, A. D., and Melville, J. G. (1981). “Nearfield performance of river diffusers.” J. Envir. Engrg. Div., 107(5), 995–1008.
Parr, A. D., and Sayre, W. W. (1979). “Multiple jets in shallow flowing receiving waters.” J. Hydraul. Div., 105(11), 1357–1374.
Platten, J. L., and Keffer, J. F. (1971). “Deflected turbulent jet flows.” J. Appl. Mech., 38E(4), 756–758.
Pun, K. L., Davidson, M. J., and Wang, H. J. (2000). “Merging jets in a co-flowing ambient fluid—A hybrid approach.” J. Hydraul. Res., 38(2), 105–114.
Rajaratnam, N. (1976). Turbulent jets, Elsevier, Amsterdam.
River2D [Computer software]. Univ. of Alberta, Edmonton, AB, Canada.
Tang, H. S., Paik, J., Sotiropoulos, F., and Khangaonkar, T. (2008). “Three-dimensional numerical modeling of initial mixing of thermal discharges at real-life configurations.” J. Hydraul. Eng., 134(9), 1210–1224.
Tian, X., Roberts, P. J. W., and Daviero, G. J. (2004). “Marine wastewater discharges from multiport diffuser—II: Unstratified flowing water.” J. Hydraul. Eng., 130(12), 1147–1155.
Tsanis, I. K., Valeo, C., and Diao, Y. (1994). “Comparison of near-field mixing zone models for multiport diffusers in the Great Lake.” Can. J. Civ. Eng., 21, 141–155.
Turner Designs. (2001). “A practical guide to flow measurement.” Turner Quantech fluorometer: Turner design guide, Waltham, MA.
VISJET 2.0 [Computer software]. Univ. of Hong Kong, Hong Kong.
Visual Plume 1.0 [Computer software]. USEPA, Washington, DC.
Wang, H. J., and Davidson, M. J. (2003). “Jet interaction in a still ambient fluid.” J. Hydraul. Eng., 129(5), 349–357.
Information & Authors
Information
Published In
Copyright
© 2011 American Society of Civil Engineers.
History
Received: Dec 23, 2009
Accepted: Nov 8, 2010
Published online: Nov 11, 2010
Published in print: Apr 1, 2011
Authors
Metrics & Citations
Metrics
Citations
Download citation
If you have the appropriate software installed, you can download article citation data to the citation manager of your choice. Simply select your manager software from the list below and click Download.