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Impingement of an axisymmetric jet on unheated and heated flat plates

Published online by Cambridge University Press:  26 April 2006

İ. Bedii Özdemir  and
J. H. Whitelaw
İ. Bedii Özdemir
Affiliation:
Department of Mechanical Engineering, Imperial College, Exhibition Road. London SW7 2BX, UK
J. H. Whitelaw
Affiliation:
Department of Mechanical Engineering, Imperial College, Exhibition Road. London SW7 2BX, UK
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Abstract

The aerodynamic and thermal aspects of the wall jet flow, formed after angled impingement of an axisymmetric jet, have been studied with emphasis on the large-scale transport of the passive scalar by the spatially coherent structures. Time-averaged and instantaneous structures of the turbulent flow were examined by visualization and local measurements of a jet arrangement with an impingement angle between the jet axis and the surface normal of 20°, a nozzle-to-plate distance to nozzle exit diameter ratio of 22, and a nozzle exit Reynolds number of 1.3 × 104.

The results show that the oblique impingement introduced vertical velocities so that boundary-layer approximations were inapplicable and led to the distribution of the time-averaged properties of the velocity and temperature field with strong azimuthal dependence, which increased gradually with angle of impingement to 40° where a sudden change of the orientation of the contours of surface pressure and temperature took place. It also led to instantaneous, spatially coherent structures which were most pronounced at an angle of 20°. These structures improved the large-scale transport of the passive scalar but, owing to the extreme regularity of their path, also led to an inactive zone near the vortex centre.

The inner region of the decelerating wall jet exhibited a momentum equilibrium layer extending to the point of radial velocity maximum and the intercept of the linear region of the semilogarithmic wall law varied in the local streamwise direction as for turbulent flows over rough walls with adverse pressure gradient. The thermal equilibrium layer had an invariant functional form but extended far beyond the point of maximum velocity.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 240 , July 1992 , pp. 503 - 532
Copyright
© 1992 Cambridge University Press

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References

Abramovich, G. N. 1963 The Theory of Turbulent Jets. MIT Press.
Bakke, P. 1957 An experimental investigation of a wall jet. J. Fluid Mech. 2, 467–472.Google Scholar
Bradshaw, P. & Love, E. M. 1959 The normal impingement of a circular air jet on a flat plate. Aero. Res. Counc. Rep. 21, p. 268.Google Scholar
Chen, T. S., Sparrow, E. M. & Mucuoglu, A. 1977 Mixed monvection in boundary layer flow on a flat plate. Intl J. Heat Transfer 99, 66–71.Google Scholar
Claus, R. W. & Vanka, S. P. 1990 Multigrid calculations of a jet in crossflow. AIAA-90–0444.Google Scholar
Didden, N. & Ho, C. M. 1985 Unsteady separation in an impinging jet. J. Fluid Mech. 160, 235–256.Google Scholar
Donaldson, C. Dup. & Snedekar, R. S. 1971 A study of free jet impingement. Part 1. Mean properties of free and impinging jets. J. Fluid Mech. 45, 281–319.Google Scholar
Donaldson, C. Dup., Snedekar, R. S. & Margolis, D. P. 1971 A study of free jet impingement. Part 2. Free jet turbulent structure and impingement heat transfer. J. Fluid Mech. 45, 477–512.Google Scholar
Foss, J. F. 1979 Measurements in a large-angle oblique jet impingement flow. AIAA J. 17, 801–802.Google Scholar
Foss, J. F. & Kleis, S. J. 1976 Mean flow characteristics for the oblique impingement of an axisymmetric jet. AIAA J. 14, 705–706.Google Scholar
Founti, M. & Laker, J. 1981 Performance characteristics of a new frequency counter interfaced to a micro-processor controlled data acquisition and processing system. Imperial College Mech. Engng Rep. FS/81/36.Google Scholar
Glauert, M. B. 1956 The wall jet. J. Fluid Mech. 1, 625–643.Google Scholar
Gutmark, E., Wolfshtein, M. & Wygnanski, I. 1978 The plane turbulent impinging jet. J. Fluid Mech. 88, 737–756.Google Scholar
Head, M. R. & Bandyopadhyay, P. 1981 New aspects of turbulent boundary-layer structure. J. Fluid Mech. 107, 297–338.Google Scholar
Hinze, J. O. 1959 Turbulence. An Introduction to its Mechanism and Theory. McGraw-Hill.
Ho, C. M. & Nosseir, N. S. 1980 Large coherent structures in an impinging jet. In Turbulent Shear Flows 2 (ed. J. S. L. Bradbury, F. Durst, B. E. Launder, F. W. Schmidt & J. H. Whitelaw), pp. 297–304, Springer
Ho, C. M. & Nosseir, N. S. 1981 Dynamics of an impinging jet. Part 1. The feedback phenomenon. J. Fluid Mech. 105, 119–142.Google Scholar
Husain, Z. D. & Hussain, A. K. M. F. 1979 Axisymmetric mixing layer: Influence of the initial and boundary conditions. AIAA J. 17, 48–55.Google Scholar
Irwin, H. P. A. 1973 Measurements in a self-preserving plane wall jet in a positive pressure gradient. J. Fluid Mech. 61, 33–63.Google Scholar
Kays, W. M. & Crawford, M. E. 1980 Convective Heat and Mass Transfer, 2nd edn. McGraw-Hill.
Kestin, J. & Wood, R. T. 1969 Enhancement of stagnation-line heat transfer by turbulence, Progr. in Heat and Mass Trans. 2, 249, Pergamon-Oxford.Google Scholar
Kreid, D. K. 1974 Laser-doppler velocimeter measurements in nonuniform flow: Error estimates. Appl. Opt. 13 1872–1881.Google Scholar
Landreth, C. C. & Adrian, R. J. 1990 Impingement of a low Reynolds number turbulent circular jet onto a flat plate at normal incidence. Exp. Fluids 9, 74–84.Google Scholar
Mele, P., Morganti, M., Scibilia, M. F. & Lasek, A. 1986 Behavior of wall jet in laminar-to-turbulent transition. AIAA J. 24, 938–939.Google Scholar
Olivari, D. 1988 Theory of Models, Course Notes on Applied Fluid Mechanics. von Karman Institute For Fluid Dynamics, Rhode-St-Genese, Belgium.
Ottino, J. M. 1989 The Kinematics of Mixing: Stretching, Chaos, and Transport. Cambridge University Press.
Ouzdemír, I. B. 1992 Impingement of single- and two-phase jets on unheated and heated flat plates. Ph.D. Thesis, University of London.
Perry, A. E., Lim, T. T. & Chong, M. S. 1980 The instantaneous velocity fields of coherent structures in coflowing jets and wakes. J. Fluid Mech. 101, 243–256.Google Scholar
Perry, A. E., Schofield, W. H. & Joubert, P. N. 1969 Rough wall turbulent boundary layers. J. Fluid Mech. 37, 383–413.Google Scholar
Poreh, M., Tsuei, Y. G. & Cermak, J. E. 1967 Investigation of a turbulent radial wall jet. Trans. ASME E: J. Appl. Mech. 34, 457–463.Google Scholar
Schmidt, G. & Tondl, A. 1986 Non-linear Vibrations. Cambridge University Press.
Schwarz, W. H. & Cosart, W. P. 1961 The two-dimensional turbulent wall jet. J. Fluid Mech. 10, 481–495.Google Scholar
Sparrow, E. M. & Minkowycz, W. J. 1962 Buoyancy effects on horizontal boundary-layer flow and heat transfer. Intl J. Heat Mass Transfer 5, 505–511.Google Scholar
Tailland, A. & Mathieu, J. 1967 Jet parietal. J. Méc. 6, 105–131.Google Scholar
Taylor, G. I. 1960 Formation of thin flat sheets of water. Phil. Trans. R. Soc. Lond. A 259, 1–17.Google Scholar
Taylor, G. I. 1966 Oblique impact of a jet on a plane surface.. Phil. Trans. R. Soc. Lond. A 260, 96–100.Google Scholar
Townsend, A. A. 1972 Mixed convection over a heated horizontal plate. J. Fluid Mech. 55, 209–227.Google Scholar
Townsend, A. A. 1976 The Structure of Turbulent Shear Flows, 2nd Edn. Cambridge University Press
Tsuji, Y., Morikawa, Y. & Sakou, M. 1977a The stability of a radial wall jet. Aeronaut. Q. 28, 247–258.Google Scholar
Tsuji, Y., Morikawa, Y., Nagatani, T. & Sakou, M. 1977b The stability of a two-dimensional wall jet. Aeronaut. Q. 28, 235–246.Google Scholar
Westley, R., Woolley, J. H. & Brosseau, P. 1972 Surface pressure fluctuations from jet impingement on an inclined flat plate. AGARD Symp. Acoustic Fatigue. AGARD-CP-113.Google Scholar
Zaman, K. B. M. Q. & Hussain, A. K. M. F. 1980 The mechanics of vortex pairing in an axisymmetric mixing layer. In Turbulent Shear Flows 2 (ed. J. S. L. Bradbury, F. Durst, B. E. Launder, F. W. Schmidt & J. H. Whitelaw), pp. 327–343. Springer.