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Turbulence in a conical diffuser with fully developed flow at entry

Published online by Cambridge University Press:  29 March 2006

P. A. C. Okwuobi
Affiliation:
Department of Mechanical Engineering, The University of Manitoba, Winnipeg, Canada
R. S. Azad
Affiliation:
Department of Mechanical Engineering, The University of Manitoba, Winnipeg, Canada

Abstract

An experimental study of the structure of turbulence in a conical diffuser having a total divergence angle of 8° and an area ratio of 4: 1 with fully developed flow at entry is described. Theresearch has been done for pipe entry Reynolds numbers of 152 000 and 293000 of profiles of the mean pressure, mean velocity, turbulence intensities, correlation coefficients and the one-dimensional energy spectra, but owing to similar behaviour for these two Reynolds numbers, data are presented for a Reynolds number of 293 000.

The results show that the rate of turbulent energy production approximately reaches a maximum value at the edge of the wall layer extending to the point of maximum u1-fluctuation. It is found that, within the layer, $\overline{u^2_1}$ varies linearly with the distance from the wall and the linear range grows with distance in the downstream direction.

The turbulent kinetic energy balance indicates that the magnitude of the energy convective diffusion due to kinetic and pressure effects is comparable with that of the energy production.

Type
Research Article
Copyright
© 1973 Cambridge University Press

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References

Ackeret, J. 1967 Cen. Motors Symp. on Internal Flow. Elsevier.
Azad, R. S. & Hummel, R. 1971 Can. J. Phys. 49, 2917.
Bakewell, P. H. & Lumley, J. L. 1967 Phys. Fluids, 10, 1880.
Bradshaw, P. 1967 Nat. Phys. Lab. Aero. Rep. no. 1220.
Champagne, F. H. & Sleicher, C. A. 1967 J. Fluid Mech. 28, 177.
Champagne, F. H., Sleicher, C. A. & Wehrmann, O. H. 1967 J. Fluid Mech. 28, 153.
Cocanower, A. B., Kline, S. J. & Johnston, J. P. 1965 Stanford University, Dept. Mech. Engng Rep. PD-10.
Cockrell, D. S. & King, A. L. 1967 Brit. Hydromech. Res. Ass. Rep. TN 902.
Fraser, H. R. 1956 Ph.D. thesis, Dept. Theoretical and Applied Mech., University of Illinois.
Gibson, A. H. 1910 Proc. Roy. SOC. A 83, 366.
Harsha, P. T. & Lee, S. C. 1970 A.I.A.A. J. 8, 1508.
Klebanoff, P. S. 1954 N.A.C.A. Tech. Note, no. 3178.
Kline, S. J., Abbott, D. E. & Fox, R. W. 1959 A.S.M.E. Tram. J. Basic Engny, 81, 321.
Laufer, J. 1951 N.A.C.A. Rep. no. 1053.
Laufer, J. 1954 N.A.C.A. Rep. no. 1174.
Lawn, C. J. 1971 J. Fluid Mech. 48, 477.
Patterson, G. N. 1938 Aircraft Engng, 10, 267.
Robertson, J. M. & Calehuff, G. L. 1957 Proc. A.S.C.E. 83, HY 5, paper 1393.
Ruetenip, J. R. & Corrsin, S. 1955 Jahre Grenzschichtforschung, pp. 446459. Brauschweig : Vieweg.
Sandborn, V. A. & Slogar, R. J. 1955 N.A.C.A. Tech. Note, no. 3264.
Schlichting, H. 1968 Boundary-Layer Theory, 6th edn. McGraw-Hill.
Sovran, G. & Klomp, E. D. 1967 Gen. Motors Symp. on Internal Flow. Elsevier.
Sprenger, H. 1959 Mitt. Inst. Aero. Zurich, no. 27. (See also 1962 Brit. Min. Aviation Rep. TIL/T. 5134.)
Trupp, A. C. Azad, R. S., Wilson, N. W. & Okwuobi, P. A. C. 1971 University of Salford Symposium on Internal Plows, paper 9.
Venturi, G. B. 1797 Nicholson's Journal of Natural Philosophy, vol. 3. London, 1802.