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Measurements of the nearly isotropic turbulence behind a uniform jet grid

Published online by Cambridge University Press:  29 March 2006

Mohamed Gad-El-Hak  and
Stanley Corrsin
Mohamed Gad-El-Hak
Affiliation:
Department of Mechanics and Materials Science, The Johns Hopkins University Present address: Department of Aerospace Engineering, University of Southern California, Los Angeles, California 90007.
Stanley Corrsin
Affiliation:
Department of Mechanics and Materials Science, The Johns Hopkins University
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Abstract

Wind-tunnel turbulence behind a parallel-rod grid with jets evenly distributed along each rod is nearly isotropic. Homogeneity improvement over prior related experiments was attained by the use of controllable nozzles. Compared with the ‘passive’ case, the downwind-jet ‘active’ grid has a smaller static pressure drop across it and gives a smaller turbulence level at a prescribed distance from it, while the upwind-jet grid gives a larger static pressure drop and larger turbulence level. ‘Counterflow injection’ generates larger turbulence energy and larger scales, both events being evidently associated with instability of the jet system. This behaviour is much like that commonly observed behind passive grids of higher solidities.

If the turbulent kinetic energy is approximated as an inverse power law in distance, the (positive) exponent decreases with increasing (downwind or upwind) jet strength, corresponding to slower absolute decay rates. No peculiar decay behaviour occurs when the jet grid is ‘self-propelled’ (zero net average force), or when the static pressure drop across it is zero.

The injection does not change the general behaviour of the energy spectra, although the absolute spectra change inasmuch as the turbulence kinetic energy changes.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 62 , Issue 1 , 8 January 1974 , pp. 115 - 143
Copyright
© 1974 Cambridge University Press

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References

Baines, W. D. & Peterson, E. G. 1951 An investigation of flow through screens Trans. A.S.M.E. 73, 467.Google Scholar
Batchelor, G. K. 1953 The Theory of Homogeneous Turbulence. Cambridge University Press.
Batchelor, G. K. & Townsend, A. A. 1947 Decay of vorticity in isotropic turbulence. Proc. Roy. Soc. A 190, 534.Google Scholar
Batchelor, G. K. & Townsend, A. A. 1948a Decay of isotropic turbulence in the initial period. Proc. Roy. Soc. A 193, 539.Google Scholar
Batchelor, G. K. & Townsend, A. A. 1948b Decay of turbulence in the final period. Proc. Roy. Soc. A 194, 527.Google Scholar
Chang, P. K. 1966 Separation of Flow. Pergamon.
Charnay, G. 1969 Etude d'une couche limite perturbée par une turbulence extérieure. Ecole Centrale Lyonnaise, Lab. de Mécanique des Fluides.Google Scholar
Comte-Bellot, G. & Corrsin, S. 1966 The use of a contraction to improve the isotropy of grid-generated turbulence J. Fluid Mech. 25, 657.Google Scholar
Comte-Bellot, G. & Corrsin, S. 1971 Simple Eulerian time correlation of full and narrow band velocity signals in grid-generated isotropic turbulence J. Fluid Mech. 48, 273.Google Scholar
Corrsin, S. 1942 Decay of turbulence behind three similar grids. Aero. Engng thesis, California Institute of Technology.
Corrsin, S. 1944 Investigation of the behaviour of parallel two-dimensional air jets. N.A.C.A. War-time Rep. W-90.Google Scholar
Corrsin, S. 1959 Outline of some topics in homogeneous turbulent flow J. Geophys. Res. 64, 2134.Google Scholar
Corrsin, S. 1963 Turbulence: experimental methods. Handbuch der Physik, vol. 8, p. 524. Springer.
Gad-El-Hak, M. 1972 Experiments on the nearly isotropic turbulence behind a jet grid. Ph.D. thesis, Dept. Mechanics & Materials Science, The Johns Hopkins University.
Guillon, O. 1968 Essais de mise au point d'une grille active à grandes mailles. Ecole Centrale Lyonnaise, Lab. de Mécanique des Fluides.
Harris, G. V. 1965 The turbulence generated by an array of parallel rods. M.S. thesis, The Johns Hopkins University.
Hinze, J. O. 1959 Turbulence. McGraw-Hill.
Hoerner, S. F. 1965 Fluid-Dynamic Drag. Published by the author, U.S.A.
Karweit, M. J. & Corrsin, S. 1969 Fluid line growth in grid-generated isotropic turbulence J. Fluid Mech. 39, 87.Google Scholar
Kistler, A. L. & Vrebalovich, T. 1961 Turbulence measurements at the 8 by 10-foot Cooperative Wind Tunnel. Jet Prop. Lab. Res. Summ. no. 36–4, p. 12.Google Scholar
Ling, S. C. & Wan, C. H. 1972 Decay of isotropic turbulence generated by a mechanically agitated grid Phys. Fluids, 15, 1363.Google Scholar
Liu, J. C. H., Greber, I. & Wiskind, H. K. 1971 Experimental measurements of gridinjection turbulent flows. Case Western Reserve University Tech. Rep. FTAS/TR-70-53.Google Scholar
Luxenberg, D. S. & Wiskind, K. 1969 Some effects of air injection on the turbulence generated by a bi-planar grid. Case Western Reserve University Tech. Rep. FTAS/TR-69-42.Google Scholar
Mathieu, J. & Alcaraz, E. 1965 Réalisation d'une soufflerie à haut niveau de turbulence Comptes Rendus, 261, 2435.Google Scholar
Monin, A. S. & Yaglom, A. M. 1971 Statistical Fluid Mechanics: The Mechanics of Turbulence, vol. 1 (English trans.). M.I.T. Press.
Naudascher, E. 1965 Flow in the wake of self-propelled bodies and related sources of turbulence J. Fluid Mech. 22, 625.Google Scholar
Naudascher, E. & Farell, C. 1970 Unified analysis of grid turbulence. J. Eng. Mech. Div., Proc. A.S.C.E., EM 2, 121.Google Scholar
Prandtl, L. & Tietjens, O. 1934 Fundamentals of Hydro- and Aero-mechanics. McGraw-Hill.
Rouse, H. 1956 Seven exploratory studies in hydraulics. J. Hyd. Div., Proc. A.S.C.E., no. 1038.Google Scholar
Simmons, L. F. G. & Salter, C. 1934 Experimental investigation and analysis of the velocity variations in turbulent flow. Proc. Roy. Soc. A 145, 212.Google Scholar
Stewart, R. W. & Townsend, A. A. 1951 Similarity and self-preservation in isotropic-turbulence. Phil. Trans. A 243, 359.Google Scholar
Tennekes, H. & Lumley, J. L. 1972 A First Course in Turbulence. M.I.T. Press.
Teunissen, H. W. 1969 An ejector-driven wind tunnel for the generation of turbulent flows with arbitrary mean velocity profile. UTIAS Tech. Note, University of Toronto, no. 133.Google Scholar
Tsuji, H. 1955 Experimental studies on the characteristics of isotropic turbulence behind two grids J. Phys. Soc. Japan, 10, 578.Google Scholar
Tsuji, H. & Hama, F. R. 1953 Experiment on the decay of turbulence behind two grids J. Aero. Sci. 20, 848.Google Scholar
Uberoi, M. S. 1963 Energy transfer in isotropic turbulence Phys. Fluids, 6, 1048.Google Scholar
Van Atta, C. W. & Chen, W. Y. 1969 Measurements of spectral energy transfer in grid turbulence J. Fluid Mech. 38, 743.Google Scholar
Von Bohl, J. G. 1940 Das Verhalten paralleler Luftstrahlen Ing.-Arch. 11, 295.Google Scholar
Wyatt, L. A. 1955 Energy and spectra in decaying homogeneous turbulence. Ph.D. thesis, University of Manchester.
Wyngaard, J. C. 1968 Measurement of small-scale turbulence structure with hot wires. J. Sci. Instrum. 1 (2), 1105.Google Scholar
Wyngaard, J. C. 1969 Spatial resolution of the vorticity meter and other hot-wire arrays J. Sci. Instrum. 2 (2), 983.Google Scholar