Hostname: page-component-cd9895bd7-8ctnn Total loading time: 0 Render date: 2024-12-23T08:17:27.711Z Has data issue: false hasContentIssue false

Effects of small streamline curvature on turbulent duct flow

Published online by Cambridge University Press:  19 April 2006

I. A. Hunt
Affiliation:
Department of Mechanical Engineering, University of Melbourne, Parkville, Australia Present address: Aeronautical Research Laboratories, Fishermen's Bend, Melbourne, Victoria, Australia.
P. N. Joubert
Affiliation:
Department of Mechanical Engineering, University of Melbourne, Parkville, Australia

Abstract

Mean velocity profiles, turbulence intensity distributions and streamwise energy spectra are presented for turbulent air flow in a smooth-walled, high aspect ratio rectangular duct with small streamwise curvature, and are compared with measurements taken in a similar straight duct.

The results for the present curved flow are found to differ significantly from those for the more highly curved flows reported previously, and suggest the need to distinguish between ‘shear-dominated’ flows with small curvature and ‘inertia-dominated’ flows with high curvature. Velocity defect and angular-momentum defect hypotheses fail to correlate the central-region mean flow data, but the wall-region data are consistent with the conventional straight-wall similarity hypothesis. A secondary flow of Taylor–Goertler vortex pattern is found to occur in the central flow region.

An examination of the flow equations yields a model for the mechanisms by which streamline curvature affects turbulent flow, in which a major effect is a direct change in the turbulent shear stress through a conservative reorientation of the turbulence intensity components. Data for the streamwise and transverse turbulence intensities show behaviour consistent with that expected from the equations, and the distribution of total turbulence energy in the central flow region is found to be nearly invariant with Reynolds number and wall curvature, in agreement with the model.

Energy spectra for the streamwise component are examined in terms of a Townsend-type two-component turbulence model. They indicate that a universal, ‘active’ component exists in all flow regions, with an ‘inactive’ component which affects only the low wavenumber spectra intensities. This is taken to imply that the effects of streamline curvature are determined by the central-region flow structure alone.

Type
Research Article
Copyright
© 1979 Cambridge University Press

Access options

Get access to the full version of this content by using one of the access options below. (Log in options will check for institutional or personal access. Content may require purchase if you do not have access.)

References

Batchelor, G. K. 1967 An Introduction to Fluid Dynamics. Cambridge University Press.
Bradshaw, P. 1967 J. Fluid Mech. 30, 241.
Bradshaw, P. 1969 J. Fluid Mech. 36, 177.
Bradshaw, P. 1972 AGARD Conf. Proc. no. CP-93, p. C-1.
Bradshaw, P. 1973 AGARDograph no. 169.
Bradshaw, P., Ferriss, D. H. & Atwell, N. P. 1967 J. Fluid Mech. 28, 593.
Clauser, F. H. 1954 J. Aero. Sci. 21, 91.
Coles, D. E. 1968 Proc. AFOSR—IFP—Stanford Conf. Comp. Turbulent Boundary Layers, vol. 2.
Comte-Bellot, G. 1963 Thesis, University of Grenoble. (Translated by P. Bradshaw as ARC Rep. no. 31 609, 1969.)
Ellis, L. B. & Joubert, P. N. 1974 J. Fluid Mech. 62, 65.
Eskinazi, S. & Erian, F. F. 1969 Phys. Fluids 12, 1988.
Eskinazi, S. & Yeh, H. 1956 J. Aero. Sci. 23, 23.
Halleen, R. M. & Johnston, J. P. 1967 Stanford University Dept. Mech. Eng. Thermosci. Div. Rep. MD—18.
Hinze, J. O. 1959 Turbulence. An Introduction to its Mechanism and Theory. McGraw-Hill.
Hunt, I. A., & Joubert, P. N. 1977 Turbulent flow in a rectangular duct. 6th Austral. Hydraul. Fluid Mech. Conf., IEAust, Adelaide, pp. 403406.Google Scholar
Hunt, I. A. & Joubert, P. N. 1978 Univ. of Melbourne, Mech. Engng Dept. Rep. FM—8.
Irwin, H. P. A. H. & Smith, P. A. 1975 Phys. Fluids 18, 624.
Johnston, J. P., Halleen, R. M. & Lezius, D. K. 1972 J. Fluid Mech. 56, 533.
Kármán, T. von 1951 Collected Works, vol. 4, p. 452. Butterworths.
Kim, H. T., Kline, S. J. & Reynolds, W. C. 1971 J. Fluid Mech. 50, 133.
Kinney, R. B. 1967 Trans. A.S.M.E. E 34, 437.
Kline, S. J., Reynolds, W. C., Schraub, F. A. & Runstadler, P. W. 1967 J. Fluid Mech. 30, 741.
Laufer, J. 1950 N.A.C.A. Tech. Note no. 2123.
Lezius, D. K. & Johnston, J. P. 1971 Stanford Univ. Dept. Mech. Engng Thermosci. Div. Rep. MD-29.Google Scholar
Marris, A. W. 1956 Can. J. Phys. 34, 1134.
Marris, A. W. 1960 Trans. A.S.M.E. D 82, 528.
Meroney, R. N. & Bradshaw, P. 1975 A.I.A.A. J. 13, 1448.
Moon, I. M. 1964 Gas Turbine Lab. MIT, Rep. no. 74.
Morrison, G. L., Perry, A. E. & Samuel, A. E. 1972 J. Fluid Mech. 52, 465.
Patel, V. C. 1965 J. Fluid Mech. 23, 185.
Patel, V. C. 1968 Aero. Res. Counc. Current Paper no. 1043.
Patel, V. C. & Head, M. R. 1969 J. Fluid Mech. 38, 181.
Perry, A. E. & Abell, C. J. 1975 J. Fluid Mech. 67, 257.
Perry, A. E. & Morrison, G. L. 1971a J. Fluid Mech. 47, 577.
Perry, A. E. & Morrison, G. L. 1971b J. Fluid Mech. 47, 765.
Prandtl, L. 1931 N.A.C.A. Tech. Mem. no. 625.
Rotta, J. C. 1967 Phys. Fluids Suppl. 9, S174.
Smith, A. M. O. 1955 Quart. Appl. Math. 13, 233.
So, R. M. C. & Mellor, G. L. 1975 Aero. Quart. 26, 25.
Tani, I. 1962 J. Geophys. Res. 67, 3075.
Taylor, G. I. 1923 Phil. Trans. A 223, 289.
Townsend, A. A. 1956 The Structure of Turbulent Shear Flow. Cambridge University Press.
Townsend, A. A. 1961 J. Fluid Mech. 11, 97.
Traugott, S. C. 1958 N.A.C.A. Tech. Note no. 4135.
Wattendorf, F. L. 1935 Proc. Roy. Soc. A 148, 565.
Wyngaard, J. C. 1968 J. Phys. E 1, 1105.
Yeh, H., Rose, W. G. & Lien, H. 1956 Final Rep. to ONR Contract NONR-248(33). Johns Hopkins Univ.