Physical Model Study of an Alternating Diffuser for Thermal Discharge
Publication: Journal of Hydraulic Engineering
Volume 137, Issue 9
Abstract
Physical model tests were conducted of the mixing of heated water from a proposed thermal diffuser. Dilutions were measured and flows imaged by a three-dimensional laser-induced fluorescence system that provides vastly more data than conventional thermocouple techniques. The flows were quite three-dimensional. For zero current speed, the effluent mixed over the water depth, but only in a limited region, and a two-layer stratified flow developed toward the edges of the effluent field and farther downstream. For zero and slow currents, the lowest surface dilution occurred where the jet centerline intersected the water surface and could be reasonably predicted by simple free-jet calculations. The prediction of an entrainment model, UM3, was close to the observed results because the flow is three-dimensional and the entraining water can be supplied from the ends. CORMIX considerably underestimated the observed dilution because it uses a two-dimensional analysis and neglects the effect of source momentum flux. Two-dimensional analyses and sectional physical models of diffusers with finite lengths should be used with caution until their limitations are better known.
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References
Adams, E. E. (1982). “Dilution analysis for unidirectional diffusers.” J. Hydraul. Div., 108(3), 327–342.
Almquist, C. W., and Stolzenbach, K. D. (1980). “Staged multiport diffusers.” J. Hydraul. Div., 106(2), 285–302.
Daviero, G. J., Roberts, P. J. W., and Maile, K. (2001). “Refractive index matching in large-scale stratified experiments.” Exp. Fluids, 31(2), 119–126.
Doneker, R. L., and Jirka, G. H. (1999). “Discussion of ‘Mixing in inclined dense jets’ by Philip J. W. Roberts, Adrian Ferrier, and Greg Daviero.” J. Hydraul. Eng., 125(3), 317–319.
Ettema, R., Arndt, R., Roberts, P. J. W., and Wahl, T. (2000). Hydraulic modeling: Concepts and practice, ASCE, Reston, VA.
Fischer, H. B., List, E. J., Koh, R. C. Y., Imberger, J., and Brooks, N. H. (1979). Mixing in inland and coastal waters, Academic, New York.
Frick, W. E. (2004). “Visual Plumes mixing zone modeling software.” Environ. Model. Software, 19, 645–654.
Frick, W. E., Roberts, P. J. W., Davis, L. R., Keyes, J., Baumgartner, D. J., and George, K. P. (2003). “Dilution models for effluent discharges (Visual Plumes).” 4th Ed., U.S. Environmental Protection Agency, Athens, GA.
Jirka, G. (1982). “Multiport diffusers for heat disposal.” J. Hydraul. Div., 108(12).
Koh, R. C. Y., Brooks, N. H., List, E. J., and Wolanski, E. J. (1974). “Hydraulic modeling of thermal outfall diffusers for the San Onofre nuclear power plant.” Rep. KH-R-30, California Institute of Technology, Pasadena, CA.
Kuang, C., and Lee, J. (2006). “Stability and mixing of a vertical axisymmetric buoyant jet in shallow water.” Environ. Fluid Mech., 6(2), 153–180.
Kuang, C. P., Lee, J. H. W., Liu, S. G., and Gu, J. (2006). “Numerical study on plume interaction above an alternating diffuser in stagnant water.” China Ocean Eng., 20(2), 289–302.
Roberts, P. J. W. (1979). “Line plume and ocean outfall dispersion.” J. Hydraul. Div., 105(4), 313–330.
Roberts, P. J. W., Ferrier, A., and Daviero, G. J. (1997). “Mixing in inclined dense jets.” J. Hydraul. Eng., 123(8), 693–699.
Roberts, P. J. W., and Snyder, W. H. (1993). “Hydraulic model study for the Boston outfall. I: Riser configuration.” J. Hydraul. Eng., 119(9), 970–987.
Seo, I. W., Kim, H. S., Yu, D., and Kim, D. S. (2001). “Performance of Tee diffusers in shallow water with crossflow.” J. Hydraul. Eng., 127(1), 53–61.
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. (2002). “3DLIF and its applications to studies of the near field mixing of wastewater discharges.” Ph.D. thesis, School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta.
Tian, X., and Roberts, P. J. W. (2003). “A 3D LIF system for turbulent buoyant jet flows.” Exp. Fluids, 35, 636–647.
Tian, X., Roberts, P. J. W., and Daviero, G. J. (2004a). “Marine wastewater discharges from multiport diffusers I: Unstratified stationary water.” J. Hydraul. Eng., 130(12), 1137–1146.
Tian, X., Roberts, P. J. W., and Daviero, G. J. (2004b). “Marine wastewater discharges from multiport diffusers II: Unstratified flowing water.” J. Hydraul. Eng., 130(12), 1147–1155.
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© 2011 American Society of Civil Engineers.
History
Received: Jun 17, 2010
Accepted: Dec 7, 2010
Published online: Dec 9, 2010
Published in print: Sep 1, 2011
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