Flow geometry effects are examined on the turbulent mixing efficiency quantified as the mixture fraction. Two different flow geometries are compared at similar Reynolds numbers, Schmidt numbers, and growth rates, with fully developed turbulence conditions. The two geometries are the round jet and the single-stream planar shear layer. At the flow conditions examined, the jet exhibits an ensemble-averaged mixing efficiency which is approximately double the value for the shear layer. This substantial difference is explained fluid mechanically in terms of the distinct large-scale entrainment and mixing-initiation environments and is therefore directly due to flow geometry effects.
Issue Section:
Technical Briefs
1.
Aguirre
, R. C.
, Catrakis
, H. J.
, Nathman
, J. C.
, and Garcia
, P. J.
, 2006, “Robust Volume-Based Approach for the Turbulent Mixing Efficiency
,” ASME J. Fluids Eng.
0098-2202, 128
, pp. 864
–873
.2.
Hale
, C. A.
, Plesniak
, M. W.
, and Ramadhyani
, S.
, 2000, “Film Cooling Effectiveness for Short Film Cooling Holes Fed by a Narrow Plenum
,” ASME J. Turbomach.
0889-504X, 122
, pp. 553
–557
.3.
Mi
, J.
, Nathan
, G. J.
, and Nobes
, D. S.
, 2001, “Mixing Characteristics of Axisymmetric Free Jets From a Contoured Nozzle, an Orifice Plate and a Pipe
,” ASME J. Fluids Eng.
0098-2202, 123
, pp. 878
–883
.4.
Jumper
, E. J.
, and Fitzgerald
, E. J.
, 2001, “Recent Advances in Aero-Optics
,” Prog. Aerosp. Sci.
0376-0421, 37
, pp. 299
–339
.5.
Dimotakis
, P. E.
, 1991, “Turbulent Free Shear Layer Mixing and Combustion
,” High Speed Flight Propulsion Systems
(Progress in Astronautics and Aeronautics Vol. 37
), S.
Murthy
and E.
Curran
, eds., AIAA
, Washington, DC
.6.
Catrakis
, H. J.
, 2004, “Turbulence and the Dynamics of Fluid Interfaces With Applications to Mixing and Aero-Optics
,” Recent Research Developments in Fluid Dynamics
, N.
Ashgriz
and R.
Anthony
, eds., Transworld Research Network Publishers
, Kerala, India
, Vol. 5
, pp. 115
–158
.7.
King
, G. F.
, Dutton
, J. C.
, and Lucht
, R. P.
, 1999, “Instantaneous, Quantitative Measurements of Molecular Mixing in the Axisymmetric Jet Near Field
,” Phys. Fluids
1070-6631, 11
, pp. 403
–416
.8.
deBruynKops
, S. M.
, and Riley
, J. J.
, 2001, “Mixing Models for Large-Eddy Simulation of Nonpremixed Turbulent Combustion
,” ASME J. Fluids Eng.
0098-2202, 123
, pp. 341
–346
.9.
Geurts
, B. J.
, 2001, “Mixing Efficiency in Turbulent Shear Layers
,” IEEE Trans. Power Syst.
0885-8950, 2
(17
), pp. 1
–23
.10.
Caulfield
, C. P.
, and Kerswell
, R. R.
, 2001, “Maximal Mixing Rate in Turbulent Stably Stratified Couette Flow
,” Phys. Fluids
1070-6631, 13
(4
), pp. 894
–900
.11.
Roshko
, A.
, 1991, “The Mixing Transition in Free Shear Flows
,” The Global Geometry of Turbulence
, J.
Jiménez
, ed., Plenum
, New York
, pp. 3
–11
.12.
Koochesfahani
, M. M.
, and Dimotakis
, P. E.
, 1986, “Mixing and Chemical Reactions in a Turbulent Liquid Mixing Layer
,” J. Fluid Mech.
0022-1120, 170
, pp. 83
–112
.13.
Mungal
, M. G.
, and Dimotakis
, P. E.
, 1984, “Mixing and Combustion With Low Heat Release in a Turbulent Shear Layer
,” J. Fluid Mech.
0022-1120, 148
, pp. 349
–382
.14.
Dahm
, W. J. A.
, and Dimotakis
, P. E.
, 1990, “Mixing at Large Schmidt Number in the Self-Similar Far Field of Turbulent Jets
,” J. Fluid Mech.
0022-1120, 217
, pp. 299
–330
.15.
Karasso
, P. S.
, and Mungal
, M. G.
, 1996, “Scalar Mixing and Reaction in Plane Liquid Shear Layers
,” J. Fluid Mech.
0022-1120, 323
, pp. 23
–63
.16.
MacKinnon
, C. G.
, and Koochesfahani
, M. M.
, 1997, “Flow Structure and Mixing in a Low Reynolds Number Forced Wake Inside a Confined Channel
,” Phys. Fluids
1070-6631, 9
, pp. 3099
–3101
.17.
Freund
, J. B.
, Moin
, P.
, and Lele
, S. K.
, 2000, “Compressibility Effects in a Turbulent Annular Mixing Layer. Part 2. Mixing of a Passive Scalar
,” J. Fluid Mech.
0022-1120, 421
, pp. 269
–292
.18.
Clemens
, N. T.
, and Mungal
, M. G.
, 1995, “Large-Scale Structure and Entrainment in the Supersonic Mixing Layer
,” J. Fluid Mech.
0022-1120, 284
, pp. 171
–216
.19.
Fernando
, H. J. S.
, and Hunt
, J. C. R.
, 1996, “Some Aspects of Turbulence and Mixing in Stably Stratified Fluids
,” Dyn. Atmos. Oceans
0377-0265, 23
, pp. 35
–62
.20.
Catrakis
, H. J.
, Aguirre
, R. C.
, Ruiz-Plancarte
, J.
, Thayne
, R. D.
, McDonald
, B. A.
, and Hearn
, J. W.
, 2002, “Large-Scale Dynamics in Turbulent Mixing and the Three-Dimensional Space-Time Behaviour of Outer Fluid Interfaces
,” J. Fluid Mech.
0022-1120, 471
, pp. 381
–408
.21.
Catrakis
, H. J.
, and Aguirre
, R. C.
, 2004, “Interfacial-Fluid Dynamics and the Mixing Efficiency of Turbulent Flows
,” Phys. Fluids
1070-6631, 16
(12
), pp. 4746
–4749
.22.
Aguirre
, R. C.
, and Catrakis
, H. J.
, 2005, “On Intermittency and the Physical Thickness of Turbulent Fluid Interfaces
,” J. Fluid Mech.
0022-1120, 540
, pp. 39
–48
.23.
Dimotakis
, P. E.
, 2000, “The Mixing Transition in Turbulent Flows
,” J. Fluid Mech.
0022-1120, 409
, pp. 69
–98
.24.
Dimotakis
, P. E.
, 2005, “Turbulent Mixing
,” Annu. Rev. Fluid Mech.
0066-4189, 37
, pp. 329
–356
.25.
Brown
, G. L.
, and Roshko
, A.
, 1974, “On Density Effects and Large Scale Structure in Turbulent Mixing Layers
,” J. Fluid Mech.
0022-1120, 64
, pp. 775
–816
.26.
Gad-el Hak
, M.
, 2000, Flow Control: Passive, Active, and Reactive Flow Management
, Cambridge University Press
, Cambridge
.27.
Sreenivasan
, K. R.
, 1991, “Fractals and Multifractals in Fluid Turbulence
,” Annu. Rev. Fluid Mech.
0066-4189, 23
, pp. 539
–600
.28.
Bisset
, D. K.
, Hunt
, J. C.
, and Rogers
, M. M.
, 2002, “The Turbulent/Non-Turbulent Interface Bounding a Far Wake
,” J. Fluid Mech.
0022-1120, 451
, pp. 381
–410
.29.
Su
, L. K.
, and Clemens
, N. T.
, 1999, “Planar Measurements of the Full Three-Dimensional Scalar Dissipation Rate in Gas-Phase Turbulent Flows
,” Exp. Fluids
0723-4864, 27
, pp. 507
–521
.30.
Jiménez
, J.
, and Martel
, C.
, 1991, “Fractal Interfaces and Product Generation in the Two-Dimensional Mixing Layer
,” Phys. Fluids A
0899-8213, 3
(5
), pp. 1261
–1268
.Copyright © 2006
by American Society of Mechanical Engineers
You do not currently have access to this content.