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Variation of enstrophy production and strain rotation relation in a turbulent boundary layer

Published online by Cambridge University Press:  28 December 2016

P. Bechlars*
Affiliation:
Aerodynamics and Flight Mechanics Research Group, University of Southampton, Southampton SO17 1BJ, UK
R. D. Sandberg
Affiliation:
Department of Mechanical Engineering, University of Melbourne, Melbourne VIC 3010, Australia
*
Email address for correspondence: patrick.bechlars@gmail.com

Abstract

The production of enstrophy is strongly coupled to the vortex stretching process that is of inherent importance to the cascading process, one of the driving processes of turbulence in a flow. In this work the enstrophy production mechanism is investigated to identify its variation in the wall-normal direction for the case of a turbulent boundary layer. Production is decomposed into its core quantities including the ratio of the principal strains and the alignment of vorticity with the eigenvectors of the strain rate tensor. The strong variations of these quantities with the wall distance are presented and explained. A self-similar shape of the probability distribution of the enstrophy production is found for regions above the buffer layer. Based on these findings we propose a modification to an existing vortex stretch model that accounts for the wall-normal variation in enstrophy production in a boundary layer. A characteristic decomposition is applied on the turbulence field that allows for the study of the individual production mechanisms of the separate structure types. This analysis reveals a potential backscatter mechanism that transfers kinetic energy from smaller scales towards larger ones, for a structure type described as unstable vortices.

Type
Papers
Copyright
© 2016 Cambridge University Press 

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References

Ashurst, W. T., Kerstein, A. R., Kerr, R. M. & Gibson, C. H. 1987 Alignment of vorticity and scalar gradient with strain rate in simulated Navier–Stokes turbulence. Phys. Fluids 30, 23432353.Google Scholar
Bechlars, P.2015 Comprehensive characterisation of turbulence dynamics with emphasis on wall-bounded flows. PhD thesis, University of Southampton.Google Scholar
Betchov, R. 1975 Numerical simulation of isotropic turbulence. Phys. Fluids 18 (10), 12301236.Google Scholar
Blackburn, H. M., Mansour, N. N. & Cantwell, B. J. 1996 Topology of fine-scale motions in turbulent channel flow. J. Fluid Mech. 310 (1), 269.Google Scholar
Buxton, O. R. H. & Ganapathisubramani, B. 2010 Amplification of enstrophy in the far field of an axisymmetric turbulent jet. J. Fluid Mech. 651, 483.CrossRefGoogle Scholar
Chong, M. S., Perry, A. E. & Cantwell, B. J. 1990 A general classification of three-dimensional flow fields. Phys. Fluids A 2 (5), 765.Google Scholar
Chong, M. S., Soria, J., Perry, A. E., Chacin, J., Cantwell, B. J. & Na, Y. 1998 Turbulence structures of wall-bounded shear flows found using DNS data. J. Fluid Mech. 357, 225247.Google Scholar
Elsinga, G. E. & Marusic, I. 2010 Evolution and lifetimes of flow topology in a turbulent boundary layer. Phys. Fluids 22 (1), 15102.Google Scholar
Ganapathisubramani, B., Lakshminarasimhan, K. & Clemens, N. T. 2008 Investigation of three-dimensional structure of fine scales in a turbulent jet by using cinematographic stereoscopic particle image velocimetry. J. Fluid Mech. 598, 141175.Google Scholar
Hamlington, P. E., Schumacher, J. & Dahm, W. J. A. 2008 Local and nonlocal strain rate fields and vorticity alignment in turbulent flows. Phys. Rev. E 77 (2), 18.Google Scholar
Jiménez, J., Hoyas, S., Simens, M. P. & Mizuno, Y. 2010 Turbulent boundary layers and channels at moderate Reynolds numbers. J. Fluid Mech. 657, 335360.CrossRefGoogle Scholar
Leung, T., Swaminathan, N. & Davidson, P. A. 2012 Geometry and interaction of structures in homogeneous isotropic turbulence. J. Fluid Mech. 710, 453481.Google Scholar
Lund, T. S. & Rogers, M. M. 1994 An improved measure of strain state probability in turbulent flows. Phys. Fluids 6 (5), 18381847.Google Scholar
Martin, J., Ooi, A., Chong, M. S. & Soria, J. 1998 Dynamics of the velocity gradient tensor invariants in isotropic turbulence. Phys. Fluids 10 (9), 2336.CrossRefGoogle Scholar
Meneveau, C. 2011 Lagrangian dynamics and models of the velocity gradient tensor in turbulent flows. Annu. Rev. Fluid Mech. 43 (1), 219245.Google Scholar
Mullin, J. A. & Dahm, W. J. A. 2006 Dual-plane stereo particle image velocimetry measurements of velocity gradient tensor fields in turbulent shear flow. I. Accuracy assessments. Phys. Fluids 18 (3), 035101.Google Scholar
Ooi, A., Martin, J., Soria, J. & Chong, M. S. 1999 A study of the evolution and characteristics of the invariants of the velocity-gradient tensor in isotropic turbulence. J. Fluid Mech. 381, 141174.Google Scholar
Perry, A. E. & Chong, M. S. 1987 A descripton of eddying motions and flow patterns using critical-point concepts. Annu. Rev. Fluid Mech. 19, 125155.Google Scholar
Perry, A. E. & Chong, M. S. 1994 Topology of flow patterns in vortex motions and turbulence. Appl. Sci. Res. 53 (3–4), 357374.CrossRefGoogle Scholar
Poinsot, T. J. & Lele, S. K. 1992 Boundary conditions for direct simulations of compressible viscous flows. J. Comput. Phys. 101 (1), 104129.Google Scholar
Sandberg, R. D. 2015 Compressible-flow DNS with application to airfoil noise. Flow Turbul. Combust. 95 (2–3), 211229.Google Scholar
Schlatter, P. & Örlü, R. 2010 Assessment of direct numerical simulation data of turbulent boundary layers. J. Fluid Mech. 659, 116126.Google Scholar
Soria, J., Sondergaard, R., Cantwell, B. J., Chong, M. S. & Perry, A. E. 1994 A study of the fine-scale motions of incompressible time-developing mixing layers. Phys. Fluids 6 (1994), 871.Google Scholar
Spalart, P. R. 1988 Direct simulation of a turbulent boundary layer up to Re 𝜃 = 1410. J. Fluid Mech. 187, 6198.Google Scholar
Taylor, G. I. 1938 Production and dissipation of vorticity in a turbulent fluid. Proc. R. Soc. Lond. A 164 (916), 1523.Google Scholar
Tennekes, H. & Lumley, J. 1972 A First Course in Turbulence. MIT Press.CrossRefGoogle Scholar
Thompson, K. W. 1990 Time dependent boundary conditions for hyperbolic systems, II. J. Comput. Phys. 89, 439461.Google Scholar
Touber, E. & Sandham, N. D. 2009 Large-eddy simulation of low-frequency unsteadiness in a turbulent shock-induced separation bubble. Theor. Comput. Fluid Dyn. 23 (2), 79107.Google Scholar
Tsinober, A. 2000 Vortex stretching versus production of strain/dissipation. In Turbulence Structure and Vortex Dynamics, pp. 164191. Cambridge University Press.Google Scholar
Tsinober, A., Kit, E. & Dracos, T. 1992 Experimental investigation of the field of velocity gradients in turbulent flows. J. Fluid Mech. 242 (-1), 169.Google Scholar
Vieillefosse, P. 1982 Local interaction between vorticity and shear in a perfect incompressible fluid. Le Journal de Physique 43, 836842.Google Scholar
Vieillefosse, P. 1984 Internal motion of a small element of fluid in an inviscid flow. Physica A 125 (1), 150162.Google Scholar
Wang, L. & Lu, X.-Y. 2012 Flow topology in compressible turbulent boundary layer. J. Fluid Mech. 703, 255278.CrossRefGoogle Scholar