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Unsteady turbulent buoyant plumes

Published online by Cambridge University Press:  05 April 2016

M. J. Woodhouse*
Affiliation:
School of Mathematics, University of Bristol, University Walk, Bristol BS8 1TW, UK School of Earth Science, University of Bristol, Wills Memorial Building, Queen’s Road, Bristol BS8 1RJ, UK
J. C. Phillips
Affiliation:
School of Earth Science, University of Bristol, Wills Memorial Building, Queen’s Road, Bristol BS8 1RJ, UK
A. J. Hogg
Affiliation:
School of Mathematics, University of Bristol, University Walk, Bristol BS8 1TW, UK
*
Email address for correspondence: mark.woodhouse@bristol.ac.uk

Abstract

We model the unsteady evolution of turbulent buoyant plumes following temporal changes to the source conditions. The integral model is derived from radial integration of the governing equations expressing the evolution of mass, axial momentum and buoyancy in the plume. The non-uniform radial profiles of the axial velocity and density deficit in the plume are explicitly captured by shape factors in the integral equations; the commonly assumed top-hat profiles lead to shape factors equal to unity. The resultant model for unsteady plumes is hyperbolic when the momentum shape factor, determined from the radial profile of the mean axial velocity in the plume, differs from unity. The solutions of the model when source conditions are maintained at constant values are shown to retain the form of the well-established steady plume solutions. We demonstrate through a linear stability analysis of these steady solutions that the inclusion of a momentum shape factor in the governing equations that differs from unity leads to a well-posed integral model. Therefore, our model does not exhibit the mathematical pathologies that appear in previously proposed unsteady integral models of turbulent plumes. A stability threshold for the value of the shape factor is also identified, resulting in a range of its values where the amplitudes of small perturbations to the steady solutions decay with distance from the source. The hyperbolic character of the system of equations allows the formation of discontinuities in the fields describing the plume properties during the unsteady evolution, and we compute numerical solutions to illustrate the transient development of a plume following an abrupt change in the source conditions. The adjustment of the plume to the new source conditions occurs through the propagation of a pulse of fluid through the plume. The dynamics of this pulse is described by a similarity solution and, through the construction of this new similarity solution, we identify three regimes in which the evolution of the transient pulse following adjustment of the source qualitatively differs.

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Papers
Copyright
© 2016 Cambridge University Press 

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References

Baines, W. D. & Turner, J. S. 1969 Turbulent buoyant convection from a source in a confined region. J. Fluid Mech. 37, 5180.CrossRefGoogle Scholar
Bender, C. M. & Orszag, S. 1978 Advanced Mathematical Methods for Scientists and Engineers. McGraw-Hill.Google Scholar
Carazzo, G., Kaminski, E. & Tait, S. 2006 The route to self-similarity in turbulent jets and plumes. J. Fluid Mech. 547, 137148.CrossRefGoogle Scholar
Craske, J. & van Reeuwijk, M. 2013 Robust and accurate open boundary conditions for incompressible turbulent jets and plumes. Comput. Fluids 86 (0), 284297.Google Scholar
Craske, J. & van Reeuwijk, M. 2015a Energy dispersion in turbulent jets. Part 1. Direct simulation of steady and unsteady jets. J. Fluid Mech. 763, 500537.CrossRefGoogle Scholar
Craske, J. & van Reeuwijk, M. 2015b Energy dispersion in turbulent jets. Part 2. A robust model for unsteady jets. J. Fluid Mech. 763, 538566.Google Scholar
Delichatsios, M. A. 1979 Time similarity analysis of unsteady buoyant plumes in neutral surroundings. J. Fluid Mech. 93, 241250.Google Scholar
Emanuel, K. A. 1994 Atmospheric Convection. Oxford University Press.Google Scholar
Ezzamel, A., Salizzoni, P. & Hunt, G. R. 2015 Dynamical variability of axisymmetric buoyant plumes. J. Fluid Mech. 765, 576611.Google Scholar
Flanders, H. 1973 Differentiation under the integral sign. Am. Math. Mon. 80 (6), 615627.CrossRefGoogle Scholar
Fox, D. G. 1970 Forced plume in a stratified fluid. J. Geophys. Res. 75 (33), 68186835.Google Scholar
Gottlieb, S. & Shu, C.-W. 1998 Total variation diminishing Runge–Kutta schemes. Math. Comput. 67 (221), 7385.Google Scholar
Hogg, A. J. & Pritchard, D. 2004 The effects of hydraulic resistance on dam-break and other shallow inertial flows. J. Fluid Mech. 501, 179212.CrossRefGoogle Scholar
Hunt, G. R. & van den Bremer, T. S. 2011 Classical plume theory: 1937–2010 and beyond. IMA J. Appl. Math. 76 (3), 424448.Google Scholar
Hunt, G. R. & Kaye, N. B. 2005 Lazy plumes. J. Fluid Mech. 533, 329338.Google Scholar
Hunt, G. R. & Kaye, N. G. 2001 Virtual origin correction for lazy turbulent plumes. J. Fluid Mech. 435, 377396.Google Scholar
Jiang, X. & Luo, K. H. 2000 Direct numerical simulation of the puffing phenomenon of an axisymmetric thermal plume. Theor. Comput. Fluid Dyn. 14 (1), 5574.CrossRefGoogle Scholar
Joseph, D. D. & Saut, J. C. 1990 Short-wave instabilities and ill-posed initial-value problems. Theor. Comput. Fluid Dyn. 1 (4), 191227.Google Scholar
Kaminski, E., Tait, S. & Carazzo, G. 2005 Turbulent entrainment in jets with arbitrary buoyancy. J. Fluid Mech. 526, 361376.Google Scholar
Kaye, N. B. 2008 Turbulent plumes in stratified environments: a review of recent work. Atmos. Ocean 46 (4), 433441.Google Scholar
Koh, R. C. Y. & Brooks, N. H. 1975 Fluid mechanics of waste-water disposal in the ocean. Annu. Rev. Fluid Mech. 7 (1), 187211.CrossRefGoogle Scholar
Kurganov, A. & Petrova, G. 2000 Central schemes and contact discontinuities. ESAIM-Math. Model. Num. 34, 12591275.Google Scholar
Kurganov, A. & Tadmor, E. 2000 New high-resolution central schemes for nonlinear conservation laws and convection–diffusion equations. J. Comput. Phys. 160 (1), 241282.CrossRefGoogle Scholar
Lax, P. D. 1973 Hyperbolic Systems of Conservation Laws and the Mathematical Theory of Shock Waves. Society for Industrial and Applied Mathematics.Google Scholar
Linden, P. F. 2000 Convection in the environment. In Perspectives in Fluid Mechanics (ed. Batchelor, G. K., Moffatt, H. K. & Worster, M. G.), pp. 287343. Cambridge University Press.Google Scholar
Linden, P. F., Lane-Serff, G. F. & Smeed, D. A. 1990 Emptying filling boxes: the fluid mechanics of natural ventilation. J. Fluid Mech. 212, 309335.Google Scholar
List, E. J. 1982 Turbulent jets and plumes. Annu. Rev. Fluid Mech. 14 (1), 189212.CrossRefGoogle Scholar
Morton, B. R. 1959 Forced plumes. J. Fluid Mech. 5, 151163.CrossRefGoogle Scholar
Morton, B. R. 1971 The choice of conservation equations for plume models. J. Geophys. Res. 76 (30), 74097416.Google Scholar
Morton, B. R., Taylor, G. & Turner, J. S. 1956 Turbulent gravitational convection from maintained and instantaneous sources. Proc. R. Soc. Lond. A 234 (1196), 123.Google Scholar
Papanicolaou, P. N. & List, E. J. 1988 Investigations of round vertical turbulent buoyant jets. J. Fluid Mech. 195, 341391.Google Scholar
Plourde, F., Pham, M. V., Kim, S. D. & Balachandar, S. 2008 Direct numerical simulations of a rapidly expanding thermal plume: structure and entrainment interaction. J. Fluid Mech. 604, 99123.Google Scholar
Priestley, C. H. B. & Ball, F. K. 1955 Continuous convection from an isolated source of heat. Q. J. R. Meteorol. Soc. 81 (348), 144157.Google Scholar
Rouse, H., Yih, C. S. & Humphreys, H. W. 1952 Gravitational convection from a boundary source. Tellus 4 (3), 201210.Google Scholar
Scase, M. M. 2009 Evolution of volcanic eruption columns. J. Geophys. Res. 114, F04003.Google Scholar
Scase, M. M., Aspden, A. J. & Caulfield, C. P. 2009 The effect of sudden source buoyancy flux increases on turbulent plumes. J. Fluid Mech. 635, 137169.Google Scholar
Scase, M. M., Caulfield, C. P. & Dalziel, S. B. 2006a Boussinesq plumes and jets with decreasing source strengths in stratified environments. J. Fluid Mech. 563, 463472.Google Scholar
Scase, M. M., Caulfield, C. P. & Dalziel, S. B. 2008 Temporal variation of non-ideal plumes with sudden reductions in buoyancy flux. J. Fluid Mech. 600, 181199.Google Scholar
Scase, M. M., Caulfield, C. P., Dalziel, S. B. & Hunt, J. C. R. 2006b Time-dependent plumes and jets with decreasing source strengths. J. Fluid Mech. 563, 443461.Google Scholar
Scase, M. M. & Hewitt, R. E. 2012 Unsteady turbulent plume models. J. Fluid Mech. 697, 455480.Google Scholar
Schmidt, W. 1941 Turbulente Ausbreitung eines Stromes erhitzter Luft. Z. Angew. Math. Mech. 21 (6), 351363 (in German).Google Scholar
Shabbir, A. & George, W. K. 1994 Experiments on a round turbulent buoyant plume. J. Fluid Mech. 275, 132.CrossRefGoogle Scholar
Shrinivas, A. B. & Hunt, G. R. 2014 Transient ventilation dynamics induced by heat sources of unequal strength. J. Fluid Mech. 738, 3464.Google Scholar
Slawson, P. R. & Csanady, G. T. 1967 On the mean path of buoyant, bent-over chimney plumes. J. Fluid Mech. 28, 311322.Google Scholar
Sparks, R. S. J., Bursik, M. I., Carey, S. N., Gilbert, J., Glaze, L. S., Sigurdsson, H. & Woods, A. W. 1997 Volcanic Plumes. Wiley.Google Scholar
Speer, K. G. & Rona, P. A. 1989 A model of an Atlantic and Pacific hydrothermal plume. J. Geophys. Res. 94 (C5), 62136220.Google Scholar
Stevens, B. 2005 Atmospheric moist convection. Annu. Rev. Earth Planet. Sci. 33 (1), 605643.CrossRefGoogle Scholar
Straneo, F. & Cenedese, C. 2015 The dynamics of Greenland’s glacial fjords and their role in climate. Annu. Rev. Marine Sci. 7 (1), 89112.Google Scholar
Turner, J. S. 1986 Turbulent entrainment: the development of the entrainment assumption, and its application to geophysical flows. J. Fluid Mech. 173, 431471.CrossRefGoogle Scholar
Vul’fson, A. N. & Borodin, O. O. 2001 Self-similar propagation regimes of a nonstationary high-temperature convective jet in the adiabatic atmosphere. J. Appl. Mech. Tech. Phys. 42 (2), 255261.CrossRefGoogle Scholar
Wang, H. & Law, A. W.-K. 2002 Second-order integral model for a round turbulent buoyant jet. J. Fluid Mech. 459, 397428.Google Scholar
Whitham, G. B. 1974 Linear and Nonlinear Waves. Wiley.Google Scholar
Woodhouse, M. J., Hogg, A. J., Phillips, J. C. & Sparks, R. S. J. 2013 Interaction between volcanic plumes and wind during the 2010 Eyjafjallajökull eruption, Iceland. J. Geophys. Res. 118 (1), 92109.Google Scholar
Woods, A. W. 1988 The fluid dynamics and thermodynamics of eruption columns. Bull. Volcanol. 50 (3), 169193.Google Scholar
Woods, A. W. 2010 Turbulent plumes in nature. Annu. Rev. Fluid Mech. 42, 391412.Google Scholar
Yannapoulos, P. C. 2006 An improved integral model for plane and round turbulent buoyant jets. J. Fluid Mech. 547, 267296.Google Scholar
Yu, H.-Z. 1990 Transient plume influence in measurement of convective heat release rates of fast-growing fires using a large-scale fire products collector. Trans. ASME J. Heat Transfer 112 (1), 186191.CrossRefGoogle Scholar
Zeldovich, Y. B. 1937 The asymptotic laws of freely-ascending convective flows. Zhur. Eksper. Teor. Fiz. 7, 14631465; (in Russian). English translation in Selected Works of Yakov Borisovich Zeldovich, (ed. J. P. Ostriker), vol. 1, 1992, pp 82–85. Princeton University Press.Google Scholar