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Aspects of the equilibrium puff in transitional pipe flow

Published online by Cambridge University Press:  21 April 2006

Promode R. Bandyopadhyay
Promode R. Bandyopadhyay
Affiliation:
Mail Stop 163, NASA Langley Research Center, Hampton, Virginia 23665–5225, USA
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Abstract

Flow-visualization studies in transitional pipe flow are used to reveal the mechanism responsible for the self-sustenance of a turbulent equilibrium puff. The upstream laminar fluid continuously enters the relatively-slower-moving turbulent puff around the pipe centre. The passage of this high-speed laminar plug flow past the slower fluid that resides near the wall at the upstream interface leads to the shedding of a train of three-dimensional wake-like vortices near the wall. A helical motion near the upstream interface is associated with the vortex-shedding process. The remainder of the puff is a cone of turbulence filled with these wake-like vortices that are decaying slowly; the prominent feature of the decay region is the longitudinal vortices that are apparently undergoing stretching. No toroidal vortex has been observed in the instantaneous flow field at the upstream interface of an individual puff. On the other hand, the wake-like vortices reported here have not been observed before because their three-dimensional and random nature does not allow detection by an ensemble-averaging that is not phase-referenced appropriately.

Type
Research Article
Information
Journal of Fluid Mechanics , Volume 163 , February 1986 , pp. 439 - 458
Copyright
© 1986 Cambridge University Press

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References

Bandyopadhyay, P. 1978 Combined flow visualization and anemometry in boundary layers. Ph.D. dissertation, University of Cambridge.
Bandyopadhyay, P. R. & Hussain, A. K. M. F. 1983 The organized motions in ‘puffs’ in transitional pipe flow. In Proc. Third Intl Symp. Flow Viz. p. 751. University of Michigan, Ann Arbor.
Batchelor, G. K. 1970 An Introduction to Fluid Dynamics. Cambridge University Press.
Cantwell, B. & Coles, D. 1983 An experimental study of entrainment and transport in the turbulent near wake of a circular cylinder. J. Fluid Mech. 136, 321–374.Google Scholar
Coles, D. 1981 Prospects for useful research on coherent structure in turbulent shear flow. Proc. Indian Acad. Sci. (Engng Sci.) 4, 111–127.Google Scholar
Fiedler, H. & Head, M. R. 1966 Intermittency measurements in a turbulent boundary layer. J. Fluid Mech. 25, 719.Google Scholar
Furuya, Y. & Miyata, M. 1972 Visual studies on the wake of a roughness element proximate to a wall. Memoirs Fac. Engng Nagoya Univ. 24, 278–293.Google Scholar
Kama, F. R. 1962 Streaklines in a perturbed shear flow. Phys. Fluids 5, 644–650.Google Scholar
Head, M. R. & Bandyopadhyay, P. 1981 New aspects of turbulent boundary-layer structure. J. Fluid Mech. 107, 297–338.Google Scholar
Kline, S. J. 1978 The role of visualization in the study of the structure of the turbulent boundary layer. Workshop on Coherent Structure of Turbulent Boundary Layers, p. 1. Lehigh University.
Matsui, T. 1981 Flow visualization studies of vortices. Proc. Indian Acad. Sci. (Engng Sci.) 4, 239–257.Google Scholar
Maxworthy, T. 1972 The structure and stability of vortex rings. J. Fluid Mech. 51, 15–32.Google Scholar
Merzkirch, W. 1974 Flow Visualization. Academic.
Moiseev, S. S., Sagdeev, R. Z., Tur, A. V., Khomenko, G. A. & Yanovskii, V. V. 1983 Theory of the origin of large-scale structures in hydrodynamic turbulence. Sov. Phys., J. Exp. Theor. Phys. 58, 1149–1153.Google Scholar
Nikuradse, J. 1949 Regularity of turbulent flow in smooth pipes. Transl. from Forschung auf den Gebeite des Ingenierwesens, Eg. B, V. 3 Forschungshelft 356, Sept.-Oct. 1932, in Purdue Res. Found. Tech. Memo. PUR 11.
Orszao, S. A. & Patera, A. T. 1981 Subcritical transition to turbulence in planar shear flows. In Transition and Turbulence (ed. R. E. Meyer), pp. 127–146. Academic.
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.Google Scholar
Perry, A. E., Lim, T. T. & Teh, E. W. 1981 A visual study of turbulent spots. J. Fluid Mech. 104, 387–405.Google Scholar
Reynolds, O. 1883 An experimental investigation of the circumstances which determine whether the motion of the water shall be direct or sinuous, and of the law of resistance in parallel channels. Phil. Trans. R. Soc. Lond. A 174, 935–982.Google Scholar
Rubin, Y., Wygnanski, I. & Haritonidis, J. H. 1980 Further observations on transition in a pipe. In Laminar—Turbulent Transition, Proc. IUTAM Symp. Sept. 16–22, 1979, Stuttgart, W. Germany, pp. 17–26. Springer.
Sato, H. & Onda, Y. 1980 The vortex shedding from a cone placed on a flat plate. In First Asian Cong. Fluid Mech. Proc. A, Paper No. A38, Indian Inst. Sci., Bangalore.
Stettler, J. C. & Hussain, A. K. M. F. 1982 An experimental study of instability of a pulsatile pipe flow using LDV. In Proc. Intl Symp. on Appl. of LDA to Fluid Mech., Lisbon, pp. 3.3–3.15.
Tsinober, A. & Levich, E. 1983 On the helical nature of three-dimensional coherent structures in turbulent flows. Phys. Lett. 99A, 321–324.Google Scholar
Weinstein, L. M. & Fitzer, P. M. 1975 Detail enhancement in prints of radiographs. Radiology 115, 726.Google Scholar
Wygnanski, I. J. & Champagne, F. H. 1973 On transition in a pipe. Part 1. The origin of puffs and slugs and the flow in a turbulent slug. J. Fluid Mech. 59, 281–335.Google Scholar
Wygnanski, I. J., Sokolov, M. & Friedman, D. 1975 On transition in a pipe. Part 2. The equilibrium puff. J. Fluid Mech. 69, 283–304.Google Scholar
Zdrakovich, M. M. 1969 Smoke observations of the formation of a KaArmaAn vortex street. J. Fluid Mech. 37, 491–496.Google Scholar