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Experiments in Fluids

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01.05.2011 | Research Article

On the generation of large-scale homogeneous turbulence

verfasst von: Jon V. Larssen, William J. Devenport

Erschienen in: Experiments in Fluids | Ausgabe 5/2011

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Abstract

An active turbulence generating grid, based on the rotating-vane design of Makita (1991), was developed for a large wind tunnel. At 2.14 m square, the grid is the largest of this type ever developed. To improve the isotropy of the turbulence generated, the grid was placed in the wind tunnel contraction. Measurements show that the grid produces a closely uniform mean flow and homogeneous isotropic turbulence to within two integral scales from the wall. By systematically varying the flow speed and parameters controlling the random motion of the vanes, grid turbulence with a wide variety of characteristics was produced and the dependence of those characteristics on the operating parameters of the grid revealed. Taylor Reynolds numbers of the grid turbulence varied from 100 to 1,360 and integral scales from 5 to almost 70 cm. The extreme cases represent some of the highest Reynolds number and largest scale homogeneous turbulent flows ever generated in a wind tunnel.

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The same results (in a slightly different form) were also independently derived by Ribner and Tucker (1953).

Note that a tilde indicates a given instance of the random parameter in question.

Kang et al. (2003) kept the cruise time constant at 1 s with a randomized rotation rate.

The Rossby number is the ratio of inertial forces to rotational forces, usually applied to the Coriolis force in the atmosphere. It has been extended here to obtain a non-dimensional grid rotation rate.

Active grid turbulence generally requires a much shorter development length than conventional grid turbulence (see e.g. Makita 1991; Larssen 2005) and all measurement points in Table 1 are believed to be contained within the initial period of decay.

This estimate is obtained by treating the wind tunnel walls as part of an infinite cascade and a blade spacing of 4.8L ₁₁.

For the test case shown in Fig. 7 \( \tilde{\Upomega } \) ranges between 2 and 6 rev/s.

In Fig. 10, Ω has been held constant at 4 Hz to keep the Rossby number from differing between the datapoints.

The turbulence kinetic energy is defined as k = (u ² + v ² + w ²)/2. In true isotropic turbulence where u ² = v ² = w ², this simply reduces to k = 3u ²/2.

Even though the modified single random forcing protocol was used by Kang et al. (2003) it has been shown here that the cruise time parameter has very little effect on the resulting turbulence intensity. This indicates that the modified single random scheme is almost equivalent to a double random forcing protocol in terms of the turbulence it produces as long as T is not set to zero.

Batchelor GK (1953) The theory of homogeneous turbulence. Cambridge University Press, CambridgeMATH

Bearman PW (1971) Corrections for the effect of ambient temperature drift on hot-wire measurements in incompressible flow. DISA Inf 11:25–30

Comte-Bellot G, Corrsin S (1966) The use of a contraction to improve the isotropy of grid generated turbulence. J Fluid Mech 25:657–682CrossRef

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 48:273–337CrossRef

Gad-el-Hak M, Corrsin S (1974) Measurements of the nearly isotropic turbulence behind a uniform jet grid. J Fluid Mech 62:115–143CrossRef

Graham JMR (1998) The effect of a two-dimensional cascade of thin streamwise plates on homogeneous turbulence. J Fluid Mech 356:125–147CrossRefMATH

Helland KN, Van Atta CW, Stegen GR (1977) Spectral energy transfer in high Reynolds number turbulence. J Fluid Mech 79:337–359CrossRef

Kang HS, Chester S, Meneveau C (2003) Decaying turbulence in an active-grid-generated flow and comparisons with large-eddy simulation. J Fluid Mech 480:129–160CrossRefMATHMathSciNet

Kistler AL, Vrebalovich T (1966) Grid turbulence at large Reynolds numbers. J Fluid Mech 26:37–47CrossRef

Larssen JV (2005) Large scale homogenous turbulence and interactions with a flat-plate cascade. Ph.D. thesis, Virginia Tech, VA, USA

Ling SC, Wan CA (1972) Decay of isotropic turbulence generated by a mechanically agitated grid. Phys Fluids 15(8):1363–1369CrossRef

Makita H (1991) Realization of a large-scale turbulence field in a small wind tunnel. Fluid Dyn Res 8:53–64CrossRef

Makita H, Miyamoto S (1983) Generation of high intensity turbulence and control of its structure in a low speed wind tunnel. In: Proceedings of 2nd Asian congress on fluid mechanics, pp 101–106

Makita H, Sassa K (1991) Active turbulence generation in a laboratory wind tunnel. In: Johansson AV, Alfredsson PH (eds) Advances in turbulence 3. Springer, Berlin, pp 497–505

Mydlarski L, Warhaft Z (1996) On the onset of high-Reynolds-number grid-generated wind tunnel turbulence. J Fluid Mech 320:331–368CrossRef

Mydlarski L, Warhaft Z (1998) Passive scalar statistics in high-Péclet-number grid turbulence. J Fluid Mech 358:135–175CrossRef

Poorte REG (1998) On the motion of bubbles in active grid generated turbulent flows. Ph.D. thesis, University of Twente, Holland

Poorte REG, Biesheuvel A (2002) Experiments on the motion of gas bubbles in turbulence generated by an active grid. J Fluid Mech 461:127–154CrossRefMATH

Pope SB (2000) Turbulent flows. Cambridge University Press, CambridgeMATH

Remillieux C et al (2008) Calibration and demonstration of the New Virginia tech anechoic wind tunnel. In: 14th AIAA-CEAS Aeroacoustics conference, Vancouver, Canada

Ribner HS, Tucker M (1953) Spectrum of turbulence in a contracting stream. NACA-1113

Roach PE (1986) The generation of nearly isotropic turbulence downstream of streamwise tube bundles. Int J Heat Fluid Flow 7(2):117–125CrossRef

Shavit U, Chigier N (1995) Development and evaluation of a new turbulence generator for atomization research. Exp Fluids 20:291–301

Simmons LFG, Salter C (1934) Experimental investigation and analysis of the velocity variations in turbulent flow. Proc R Soc Lond A 145:212–234CrossRef

Srdic A, Fernando HJS, Montenegro L (1995) Generation of nearly isotropic turbulence using two oscillating grids. Exp Fluids 20:395–397

Tassa Y, Kamotani Y (1974) Experiments on turbulence behind a grid with jet injection in downstream and upstream direction. Phys Fluids 18(4):411–414CrossRef

Taylor GI (1935) Statistical theory of turbulence, parts I–IV. Proc R Soc Lond A 151:421–478CrossRef

Thole KA, Bogard DG, Whan-Tong JL (1994) Generating high freestream turbulence levels. Exp Fluids 17:375–380CrossRef

Thompson SM, Turner JS (1975) Mixing across an interface due to turbulence generated by an oscillating grid. J Fluid Mech 67:349–368CrossRef

Uberoi MS (1956) Effect of wind-tunnel contraction on free-stream turbulence. J Aeronaut Sci 23:754–764

Uberoi MS, Wallis S (1967) Effects of grid geometry on turbulence decay. Phys Fluids 10(6):1216–1224CrossRef

Villermaux E, Sommeria J, Gagne Y, Hopfinger EJ (1991) Oscillatory instability and genesis of turbulence behind a high solidity grid. Eur J Mech B/Fluids 10(4):427–439

Wittmer KS, Devenport WJ, Zsoldos JS (1998) A four-sensor hot-wire probe system for three-component velocity measurement. Exp Fluids 24:416–423. See also: 1999, Exp Fluids 27:U1

Titel: On the generation of large-scale homogeneous turbulence
verfasst von: Jon V. Larssen
William J. Devenport
Publikationsdatum: 01.05.2011
Verlag: Springer-Verlag
Erschienen in: Experiments in Fluids / Ausgabe 5/2011
Print ISSN: 0723-4864
Elektronische ISSN: 1432-1114
DOI: https://doi.org/10.1007/s00348-010-0974-1

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