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Use of a pseudo-turbulent signal to calibrate an intermittency measuring circuit

Published online by Cambridge University Press:  29 March 2006

R. A. Antonia  and
J. D. Atkinson
R. A. Antonia
Affiliation:
Department of Mechanical Engineering, University of Sydney
J. D. Atkinson
Affiliation:
Department of Mechanical Engineering, University of Sydney
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Abstract

Measurements of the intermittency factor γ and in particular the crossing frequency fγ of the turbulent/non-turbulent interface in the outer regions of various turbulent shear flows depend strongly on the settings of the intermittency meter used. Two methods of calibrating an intermittency meter of conventional design are described. In the first, turbulent and non-turbulent signals are simulated and switched at random times using an analog computer. Particular attention is given to the spectra of the switching and turbulent signals but the non-turbulent signal is assumed to have the same spectrum as the turbulent signal. In the second method, the same switching process is applied to two real signals, obtained in the fully turbulent and irretational flow regions associated with a turbulent jet with a co-flowing external air stream. A rather simple calibration procedure derived using the results of both methods is applied to the measurements of γ and fγ in the same jet. It is suggested that the simulation process adopted here could be useful in inferring properties of intermittent turbulent flows.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 64 , Issue 4 , 24 July 1974 , pp. 679 - 699
Copyright
© 1974 Cambridge University Press

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References

Antonia, R. A. 1972 Conditionally sampled measurements near the outer edge of a turbulent boundary layer. J. Fluid Mech. 56, 1.Google Scholar
Antonia, R. A. & Atkinson, J. D. 1973 High-order moments of Reynolds shear stress fluctuations. J. Fluid Mech. 58, 481.Google Scholar
Antonia, R. A. & Bradshaw, P. 1971 Conditional sampling of turbulent shear flows. Imp. Coll. Aero. Rep. no. 71–04.Google Scholar
Antonia, R. A. & Stellema, L. 1973 Description of an intermittency meter. Charles Kolling Res. Lab., Dept. Mech. Engng, University of Sydney, Tech. Note, D-8.Google Scholar
Atkinson, J. D. 1972 Analog computer simulation of turbulence signals. Charles Kolling Res. Lab., Dept. Mech. Engng, University of Sydney, Tech. Note, F-42.Google Scholar
Bradbury, L. J. S. 1965 The structure of a self-preserving turbulent plane jet. J. Fluid Mech. 23, 31.Google Scholar
Bradshaw, P. 1966 The turbulence structure of equilibrium boundary layers. N.P.L. Aero. Rep. no. 1184.Google Scholar
Bradshaw, P. 1972 An introduction to conditional sampling of turbulent flows. Imp. Coll. Aero Rep. no. 72-18.Google Scholar
Bradshaw, P. & Murlis, J. 1973 On the measurement of intermittency in turbulent flow. Imp. Coll. Aero. Tech. Note, no. 73–108.Google Scholar
Corrsin, S. & Kistler, A. L. 1955 Free-stream boundaries of turbulent flows. N.A.C.A. Rep. no. 1244.Google Scholar
Demetriades, A. 1968 Turbulent front structure of an axisymmetric compressible wake. J. Fluid Mech. 34, 465.Google Scholar
Dumas, R. 1964 Contribution a 1'étude des spectres de turbulence. Publ. Sci. Tech. Min. de l'Air, no. 404.Google Scholar
Frenkiel, F. N. & Klebanoff, P. S. 1971 Statistical properties of velocity derivatives in a turbulent field. J. Fluid Mech. 48, 183.Google Scholar
Hedley, T. B. & Keffer, J. F. 1974a Turbulentlnon-turbulent decisions in an intermittent flow. J. Fluid Mech. 64, 625.Google Scholar
Hedley, T. B. & Keffer, J. F. 1974b Some turbulentlnon-turbulent properties of the outer intermittent region of a boundary layer. J. Fluid Mech. 64, 645.Google Scholar
Kaplan, R. E. & Laufer, J. 1968 The intermittently turbulent region of the boundary layer. Proc. 12th Int. Cong. Appl. Mech., p. 236. Springer.
Kibens, V. & Kovasznay, L. S. G. 1970 Detection of the turbulent-non-turbulent inter-face. Dept. Mech., The Johns Hopkins University, Rep. no. 1.Google Scholar
Klebanoff, P. S. 1955 Characteristics of turbulence in a boundary layer with zero pressure gradient. N.A.C.A. Rep. no. 1247.Google Scholar
Kovasznay, L. S. G., Kibens, V. & Blackwelder, R. F. 1970 Large-scale motion in the intermittent region of a turbulent boundary layer. J. Fluid Mech. 41, 283.Google Scholar
Kuo, A. Y. S. & Corrsin, S. 1971 Experiments on internal intermittency and fine-structure distribution functions in fully turbulent fluid. J. Fluid Mech. 50, 285.Google Scholar
Lu, S.-S. & Willmarth, W. W. 1972 The structure of Reynolds stress in a turbulent boundary layer. Dept. Aerospace Engng, University of Michigan, Tech. Rep. no. 021490.Google Scholar
Narahari, RAOK., Narasimha, R. & Badri Narayanan, M. A. 1971 The bursting phenomenon in a turbulent boundary layer. J. Fluid Mech. 48, 339.Google Scholar
Sandborn, V. A. 1959 Measurements of intermittency of turbulent motion in a boundary layer. J. Fluid Mech. 6, 231.Google Scholar
Seshagiri, B. V. & Bragg, G. M. 1972 Uncertainty in measurement of intermittency in turbulent free shear flows. A.I.A.A. J. 10, 542.Google Scholar
Sherman, D. 1972 Some measurements of the intermittency function in an open channel flow in the region immediately downstream of a natural transition. Dept. Supply, Aero. Res. Lab. Structures & Materials Note, no. 374.Google Scholar
Thomas, R. M. 1973 Conditional sampling and other measurements in a plane turbulent wake. J. Fluid Mech. 57, 549.Google Scholar
Townsend, A. A. 1949 The fully developed turbulent wake of a circular cylinder. Austr. J. Sci. Res. A 2, 451.Google Scholar
Wyonanski, I. & Fiedler, H. E. 1970 The two-dimensional mixing region. J. Fluid Mech. 41, 327.Google Scholar