Characteristics of a Three-Dimensional Square Jet in the Vicinity of a Free Surface
Publication: Journal of Hydraulic Engineering
Volume 135, Issue 11
Abstract
The characteristics of a turbulent jet issuing from a square cross section nozzle in the vicinity of a free surface are presented. Two-component laser Doppler measurements were obtained at eight stations downstream of the nozzle exit, up to a distance of 27 nozzle widths. The Reynolds number based on the exit condition was 40,000. The proximity of the free surface influence the turbulence levels in the jet. Both confinement effects and axis switching influence the evolution of the velocity profiles downstream of the nozzle. The shear stress profiles indicate the formation of a wider mixing zone in the bottom portion of the jet in regions closer to the nozzle exit. Through quadrant decomposition, ejection, and entraining type events were identified. The magnitudes of the peak shear stress in the various quadrants indicate differences in the turbulence characteristics on the top and bottom portions of the jet. As distinguished in the extreme event plots, there are differences in the magnitudes of the peaks and also in their locations.
Get full access to this article
View all available purchase options and get full access to this article.
References
Anthony, D. G., and Willmarth, W. W. (1992). “Turbulence measurements in a round jet beneath a free surface.” J. Fluid Mech., 243, 699–720.
Antonia, R. A., and Xu, G. (2002). “Effect of different initial conditions on a turbulent round free jet.” Exp. Fluids, 33, 677–683.
Grinstein, F. F., and DeVore, C. R. (1996). “Dynamics of coherent structures and transition to turbulence in free square jets.” Phys. Fluids, 8(5), 1237–1250.
Grinstein, F. F., Gutmark, E., and Parr, T. (1995). “Near field dynamics of subsonic free square jets. A computational and experimental study.” Phys. Fluids, 7(6), 1483–1497.
Hussein, J. H., Capp, S. P., and George, W. K. (1994). “Velocity measurements in a high Reynolds-number, momentum-conserving, axi-symmetric, turbulent jet.” J. Fluid Mech., 258, 31–75.
Kang, S., Patil, B., and Roy, R. P. (2001). “Effects of coincidence window and measuring volume size on laser Doppler velocimetry measurement of turbulence.” Exp. Fluids, 30, 365–370.
Liepmann, D., and Gharib, M. (1992). “The role of streamwise vorticity in the near-field entrainment of round jets.” J. Fluid Mech., 245, 643–668.
Madnia, K., and Bernal, L. (1994). “Interaction of a turbulent round jet with the free surface.” J. Fluid Mech., 261, 305–332.
Nezu, I. (2005). “Open-channel flow turbulence and its research prospect in the century.” J. Hydraul. Eng., 131(4), 229–246.
Rajaratnam, N. (1976). Turbulent jets, Elsevier Science, Amsterdam.
Sankar, G. (2005). “Characteristics of confined square jets in the vicinity of a free surface.” M.A.Sc. thesis, Univ. of Windsor, Ont., Canada.
Sankar, G., Balachandar, R., and Carriveau, R. (2008). “Three-dimensional square jet characteristics in the vicinity of a free surface for varying tailwater levels.” Technical Rep. No. 2008-06-87-001, Univ. of Windsor, Ont., Canada.
Sforza, P. M., Steiger, M. H., and Trentacoste, N. (1966). “Studies on three-dimensional viscous jets.” AIAA J., 4(5), 800–806.
Shineeb, A., Bugg, J., and Balachandar, R. (2008). “Quantitative investigation of cortical structures in the near-exit region of an axisymmetric turbulent jet.” J. Turbul., 9, N 19.
Wygnanski, I., and Fiedler, H. (1969). “Some measurements in the self-preserving jet.” J. Fluid Mech., 38, 577–612.
Information & Authors
Information
Published In
Journal of Hydraulic Engineering
Volume 135 • Issue 11 • November 2009
Pages: 989 - 994
Copyright
© 2009 ASCE.
History
Received: Jan 19, 2006
Accepted: Jun 3, 2009
Published online: Oct 15, 2009
Published in print: Nov 2009
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.