Buoyancy Effect on Turbulent Round Jet under Regular Waves
Publication: Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 139, Issue 3
Abstract
The mean and turbulence properties of a turbulent buoyant jet discharged at middepth in a direction opposite to the wave propagation direction are experimentally investigated using particle image velocimetry. Three kinds of effluent jets are employed for examining the effects of buoyancy on the interactions of a horizontal round jet in both the jet’s potential core region and the self-similar region with regular waves. By comparing the buoyant jet in a stagnant ambient environment and a wave field, the experiment demonstrates that the widths of the positive and negative jets increase significantly because of the buoyancy effect and the wave dispersion effect—a clear indication of enhanced jet diffusion. As expected, the turbulence intensity and Reynolds stress of the buoyant jet is also significantly influenced when the jet is acted upon by waves. To quantify this influence, the eddy viscosity is calculated on the basis of the measurements. An examination of the buoyant jet’s energy budget shows that when the jet is under the waves, its mean kinetic energy decreases while its turbulent kinetic energy increases, indicating an increase in turbulence production. By examining the near-field property, it is found that the turbulence production, advection, and dissipation terms of the buoyant jet under waves are greater than those of a buoyant jet in a stagnant environment, owing to the greater interaction between the buoyancy effects and the water waves near the free surface.
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Acknowledgments
We express sincere gratitude to the National Science Council in Taiwan and the Sinotech Foundation for Research and Development of Engineering Sciences and Technology for their financial support (grant number: NSC 100-2628-E-006-017). This research was, in part, supported by the Ministry of Education, Taiwan, R.O.C. The Aim for the Top University Project to National Cheng-Kung University. We are grateful to the anonymous reviewers for their valuable comments and suggestions. T. W. Hsu wishes to acknowledge the support by the Research Center for Energy Technology and Strategy, NCKU and the Research Center for Ocean Energy and Strategy, NTOU.
References
Chang, K.-A., and Cowen, E. A. (2002). “Turbulent Prandtl number in neutrally buoyant turbulent round jet.” J. Eng. Mech., 128(10), 1082–1087.
Chang, K.-A., Ryu, Y., and Mori, N. (2009). “Parameterization of neutrally buoyant horizontal round jet in wave environment.” J. Waterway, Port, Coastal, Ocean Eng., 135(3), 100–107.
Chin, D. A. (1987). “Influence of surface waves on outfall dilution.” J. Hydraul. Eng., 113(8), 1006–1018.
Chin, D. A. (1988). “Model of buoyant-jet-surface-wave interaction.” J. Waterway, Port, Coastal, Ocean Eng., 114(3), 331–345.
Chyan, J.-M., and Hwung, H.-H. (1993). “On the interaction of a turbulent jet with waves.” J. Hydraul. Res., 31(6), 791–810.
Cowen, E. A., Chang, K.-A., and Liao, Q. (2001). “A single-camera coupled PTV–LIF technique.” Exp. Fluids, 31(1), 63–73.
Cowen, E. A., Sou, I. M., Liu, P. L. F., and Raubenheimer, R. (2003). “Particle image velocimetry measurements within a laboratory-generated swash zone.” J. Eng. Mech., 129(10), 1119–1129.
de Jong, J., et al. (2009). “Dissipation rate estimation from PIV in zero-mean isotropic turbulence.” Exp. Fluids, 46(3), 499–515.
Doron, P., Bertuccioli, L., Katz, J., and Osborn, T. R. (2001). “Turbulence characteristics and dissipation estimates in the coastal ocean bottom boundary layer from PIV data.” J. Phys. Oceanogr., 31(8), 2108–2134.
Gargett, A. E., Osborn, T. R., and Nasmyth, P. W. (1984). “Local isotropy and the decay of turbulence in a stratified fluid.” J. Fluid Mech., 144, 231–280.
George, W. K., and Hussein, H. J. (1991). “Locally axisymmetric turbulence.” J. Fluid Mech., 233, 1–23.
Govender, K., Mocke, G. P., and Alport, M. J. (2004). “Dissipation of isotropic turbulence and length-scale measurements through the wave roller in laboratory spilling waves.” J. Geophys. Res., 109(C8), 5115–5124.
Hsiao, S.-C., Hsu, T.-W., Lin, J.-F., and Chang, K.-A. (2011). “Mean and turbulence properties of neutrally buoyant round jet in wave environment.” J. Waterway, Port, Coastal, Ocean Eng., 137(3), 109–122.
Huang, Z. C., Hsiao, S. C., Hwung, H. H., and Chang, K. A. (2009). “Turbulence and energy dissipations of surf-zone spilling breakers.” Coast. Eng., 56(7), 733–746.
Huang, Z. C., Hwung, H. H., Hsiao, S. C., and Chang, K. A. (2010). “Laboratory observation of boundary layer flow under spilling breakers in surf zone using particle image velocimetry.” Coast. Eng., 57(3), 343–357.
Hussein, H. J., Capp, S. P., and George, W. K. (1994). “Velocity measurements in a high-Reynolds-number, momentum-conserving, axis-symmetric, turbulent jet.” J. Fluid Mech., 258, 31–75.
INSIGHT 6 [Computer software]. Shoreview, MN, TSI, Inc.
Jirka, G. H. (2004). “Integral model for turbulent buoyant jets in unbounded stratified flows. Part I: Single round jet.” Environ. Fluid Mech., 4(1), 1–56.
Jirka, G. H. (2006). “Integral model for turbulent buoyant jets in unbounded stratified flows Part 2: Plane jet dynamics resulting from multiport diffuser jets.” Environ. Fluid Mech., 6(1), 43–100.
Johnston, A. J., Nguyen, N., and Voker, R. E. (1993). “Round buoyant jet entering shallow water in motion.” J. Hydraul. Eng., 119(12), 1364–1382.
Johnston, A. J., and Volker, R. E. (1993). “Round buoyant jet entering shallow water.” J. Hydraul. Res., 31(1), 121–138.
Kimmoun, O., and Branger, H. (2007). “A particle images velocimetry investigation on laboratory surf-zone breaking waves over a sloping beach.” J. Fluid Mech., 588, 353–397.
Kolmogorov, A. N. (1941). “The local structure of turbulence in an incompressible viscous fluid for very large Reynolds numbers.” Dokl. Akad. Nauk SSSR, 30, 299–303.
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., and Neville-Jones, P. (1987). “Initial dilution of horizontal jet in crossflow.” J. Hydraul. Eng., 113(5), 615–629.
List, E. J. (1982). “Turbulent jets and plumes.” Annu. Rev. Fluid Mech., 14, 189–212.
Liu, S., Meneveau, C., and Katz, J. (1994). “On the properties of similarity subgrid-scale models as deduced from measurements in a turbulent jet.” J. Fluid Mech., 275, 83–119.
Mansard, E. P. D., and Funke, E. R. (1980). “The measurement of incident and reflected spectra using a least squares method.” Proc., 17th Int. Conf. Coastal Eng, ASCE, Reston, VA, 154–172.
Mori, N., and Chang, K.-A. (2003). “Experimental study of a horizontal jet in a wavy environment.” J. Eng. Mech., 129(10), 1149–1155.
Mossa, M. (2004). “Experimental study on the interaction of non-buoyant jets and waves.” J. Hydraul. Res., 42(1), 13–28.
Panchapakesan, N. R., and Lumley, J. L. (1993). “Turbulence measurements in axisymmetric jets of air and helium. Part 1. Air jet.” J. Fluid Mech., 246, 197–223.
Papanicolaou, P. N., and List, E. J. (1988). “Investigations of round turbulent buoyant jets.” J. Fluid Mech., 195, 341–391.
Pope, S. B. (2000). Turbulent flows, Cambridge University Press, Cambridge, U.K.
Ryu, Y., Chang, K.-A., and Mori, N. (2005). “Dispersion of neutrally buoyant horizontal round jet in wave environment.” J. Hydraul. Eng., 131(12), 1088–1097.
Shao, D., and Law, A. W.-K. (2009). “Turbulent mass and momentum transport of a circular offset dense jet.” J. Turbul., 10(40), 1–24.
Shao, D., and Law, A. W.-K. (2011). “Boundary impingement and attachment of horizontal offset dense jets.” J. Hydro-Environ. Res., 5(1), 15–24.
Sheng, J., Meng, H., and Fox, R. O. (2000). “A large eddy PIV method for turbulence dissipation rate estimation.” Chem. Eng. Sci., 55(20), 4423–4434.
Sobey, R. J., Johnston, A. J., and Keane, R. D. (1988). “Horizontal round buoyant jet in shallow water.” J. Hydraul. Eng., 114(8), 910–929.
Tam, B. Y.-F., and Li, C.-W. (2008). “Flow induced by a turbulent jet under random waves.” J. Hydraul. Res., 46(6), 820–829.
Tanaka, T., and Eaton, J. K. (2007). “A correction method for measuring turbulence kinetic energy dissipation rate by PIV.” Exp. Fluids, 42(6), 893–902.
Tennekes, L., and Lumley, J. L. (1972). A first course in turbulence, MIT Press, Cambridge, MA.
Turner, J. S. (1966). “Jets and plumes with negative or reversing buoyancy.” J. Fluid Mech., 26(04), 779–792.
Wang, H., and Law, A. W.-K. (2002). “Second-order integral model for a round turbulent buoyant jet.” J. Fluid Mech., 459, 397–428.
Weisgraber, T. H., and Liepmann, D. (1998). “Turbulent structure during transition to self-similarity in a round jet.” Exp. Fluids, 24(3), 210–224.
Wright, S. J. (1977). “Mean behavior of buoyant jets in a crossflow.” J. Hydr. Div., 103(5), 499–513.
Yannopoulos, P. C. (2010). “Advanced integral model for groups of interacting round turbulent buoyant jets.” Environ. Fluid Mech., 10(4), 415–450.
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Published In
Journal of Waterway, Port, Coastal, and Ocean Engineering
Volume 139 • Issue 3 • May 2013
Pages: 190 - 208
Copyright
© 2013 American Society of Civil Engineers.
History
Received: Nov 9, 2011
Accepted: May 17, 2012
Published online: May 22, 2012
Published in print: May 1, 2013
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