Abstract
The dynamics of the three-dimensional evolution of coherent vortical structures forming in moderate Reynolds number free, shear flows is discussed. Laboratory experiments of the evolution of transitional plane mixing layers, wakes and axisymmetric jets, developing from initially laminar conditions, subjected to temporal and spatially varying periodic perturbations are analyzed by means of an inviscid vortex dynamics model of the evolution of one or several layers of vortex filaments in which the initial vorticity is discretized. For planar and axisymmetric flow configurations, the formation and evolution of streamwise vortex tubes and their interaction with the primary, two-dimensional, coherent vortical structure is analyzed. The symmetry features and the topological transitions of the three-dimensional vorticity field resulting from the growth of the initial perturbations is studied for both the planar and axisymmetric cases.
Comparison between the experimental results and the numerical simulations indicates that important features of the three-dimensional evolution of the large scale vortical structures can be reproduced by inviscid vortex dynamics. Vortex stretching in the braid regions appears to be the primary mechanism for the formation of concentrated streamwise vorticity in free shear flows such as mixing layers, wakes and jets.
Several topological modes of the evolving three-dimensional vorticity field having different symmetry properties are shown to exist in both mixing layers and wake flows.
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References
ASHURST, W.T. and MEIBURG, E. Three-dimensional shear layers via vortex dynamics. J. Fluid Mech. 189, p. 87. 1988.
BROWAND, F.K. and TROUTT, T.R. The turbulent mixing layer: geometry of large vortices. J. Fluid Mech. 158, p. 489. 1985.
CANTWELL, B.J. Organized motion in turbulent flow. Ann. Rev. Fluid Mech. 13, p. 457. 1981.
CHEN, L.D. and ROQUEMORE, W.M. Visualization of jet flames. Combustion and Flame. 66, p. 81, 1986.
GILBERT, N. and KLEISER, L. Near-wall phenomena in transition to turbulence. To appear in Proceedings of the International Seminar on Near-Wall Turbulence, Dubrovnik, Yugoslavia, Hemisphere Press. 1988.
HO, C.M. and HUERRE, P. Perturbed free shear layers. Ann. Rev. Fluid Mech. 16, p. 365. 1984.
LASHERAS, J.C., CHO, J.S. and MAXWORTHY, T. On the origin and evolution of streamwise vortical structures in a plane free shear-layer. J. Fluid Mech. 172, p. 231. 1986
LASHERAS, J.C. and CHOI, H. Three-dimensional instability of a plane, free shear layer: an experimental study of the formation and evolution of streamwise vortices. J. Fluid Mech. 189, p. 53. 1988
LASHERAS, J.C. and MEIBURG, E. Three-dimensinal vorticity modes in the wake of a flat plate. (in press), Physics of Fluids A. 1990.
LEONARD, A. Computing three-dimensional incompressible flows with vortex elements. Ann. Rev. Fluid Mech. 17, p. 523. 1985.
LIN, S.J. and CORCOS, G.M. The mixing layer: deterministic models of a turbulent flow. Part 3: The effect of plane strain on the dynamics of streamwise vortices. J. Fluid Mech. 141, p. 139. 1984.
LIU, J.T.C. Coherent structures in transitional and turbulent free shear flows. Ann. Rev. Fluid Mech. 21, p. 285. 1989.
MEIBURG, E., LASHERAS, J.C. and ASHURST, W.T. Topology of the vorticity field in three-dimensional shear layers and wakes. Fluid Dynamics Research 3, p. 140. 1987.
MEIBURG, E. and LASHERAS, J.C. Experimental and numerical investigation of the three-dimensional transition in plane wakes. J. Fluid Mech. 190, p. 1. 1988.
MEIBURG, E., LASHERAS, J.C. and MARTIN, J.E. Experimental and numerical analysis of the three-dimensional evolution of an axisymmetric jet. (in press) Turbulent Shear Flows 7. Springer-Verlag. F. Durst Ed. 1990.
PAREKH, D.E. and REYNOLDS, W.C. Bifurcating air jets at high subsonic speeds. Presentation at the Sixth Symposium on Turbulent Shear Flows, Toulouse, France. 1987.
ROSHKO, A. Structure of turbulent shear flows: a new look. AIAA J. 14, 1349. 1976
TOWNSEND, A.A. Flow patterns of large eddies in a wake and in a boundary layer. J. Fluid Mech. 95, 515. 1979.
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© 1991 Springer Science+Business Media Dordrecht
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Lasheras, J.C., Meiburg, E. (1991). On the Three-Dimensional Dynamics of Coherent Vortical Structures Forming in Free, Shear Flows. In: Metais, O., Lesieur, M. (eds) Turbulence and Coherent Structures. Fluid Mechanics and Its Applications, vol 2. Springer, Dordrecht. https://doi.org/10.1007/978-94-015-7904-9_6
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DOI: https://doi.org/10.1007/978-94-015-7904-9_6
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