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Toward vortex identification based on local pressure-minimum criterion in compressible and variable density flows

Published online by Cambridge University Press:  02 July 2018

Jie Yao
Affiliation:
Department of Mechanical Engineering, Texas Tech University, Lubbock, TX 79409, USA
Fazle Hussain*
Affiliation:
Department of Mechanical Engineering, Texas Tech University, Lubbock, TX 79409, USA
*
Email address for correspondence: [email protected]

Abstract

We propose a dynamical vortex definition (the ‘$\unicode[STIX]{x1D706}_{\unicode[STIX]{x1D70C}}$ definition’) for flows dominated by density variation, such as compressible and multi-phase flows. Based on the search of the pressure minimum in a plane, $\unicode[STIX]{x1D706}_{\unicode[STIX]{x1D70C}}$ defines a vortex to be a connected region with two negative eigenvalues of the tensor $\unicode[STIX]{x1D64E}^{M}+\unicode[STIX]{x1D64E}^{\unicode[STIX]{x1D717}}$. Here, $\unicode[STIX]{x1D64E}^{M}$ is the symmetric part of the tensor product of the momentum gradient tensor $\unicode[STIX]{x1D735}(\unicode[STIX]{x1D70C}\unicode[STIX]{x1D66A})$ and the velocity gradient tensor $\unicode[STIX]{x1D735}\unicode[STIX]{x1D66A}$, with $\unicode[STIX]{x1D64E}^{\unicode[STIX]{x1D717}}$ denoting the symmetric part of momentum-dilatation gradient tensor $\unicode[STIX]{x1D735}(\unicode[STIX]{x1D717}\unicode[STIX]{x1D70C}\unicode[STIX]{x1D66A})$, and $\unicode[STIX]{x1D717}\equiv \unicode[STIX]{x1D735}\boldsymbol{\cdot }\unicode[STIX]{x1D66A}$, the dilatation rate scalar. The $\unicode[STIX]{x1D706}_{\unicode[STIX]{x1D70C}}$ definition is examined and compared with the $\unicode[STIX]{x1D706}_{2}$ definition using the analytical isentropic Euler vortex and several other flows obtained by direct numerical simulation (DNS) – e.g. liquid jet breakup in a gas, a compressible wake, a compressible turbulent channel and a hypersonic turbulent boundary layer. For low Mach number ($M\lesssim 5$) compressible flows, the $\unicode[STIX]{x1D706}_{2}$ and $\unicode[STIX]{x1D706}_{\unicode[STIX]{x1D70C}}$ structures are nearly identical, so that the $\unicode[STIX]{x1D706}_{2}$ method is still valid for low $M$ compressible flows. But, the $\unicode[STIX]{x1D706}_{\unicode[STIX]{x1D70C}}$ definition is needed for studying vortex dynamics in highly compressible and strongly varying density flows.

Type
JFM Papers
Copyright
© 2018 Cambridge University Press 

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References

Chakraborty, P., Balachandar, S. & Adrian, R. J. 2005 On the relationships between local vortex identification schemes. J. Fluid Mech. 535, 189214.Google Scholar
Chakraborty, N., Wang, L., Konstantinou, I. & Klein, M. 2017 Vorticity statistics based on velocity and density-weighted velocity in premixed reactive turbulence. J. Turbul. 18 (9), 129.Google Scholar
Chong, M. S., Perry, A. E. & Cantwell, B. J. 1990 A general classification of three-dimensional flow fields. Phys. Fluids A 2 (5), 765777.Google Scholar
Cucitore, R., Quadrio, M. & Baron, A. 1999 On the effectiveness and limitations of local criteria for the identification of a vortex. Eur. J. Mech. (B/Fluids) 18 (2), 261282.Google Scholar
Duan, L., Choudhari, M. M. & Zhang, C. 2016 Pressure fluctuations induced by a hypersonic turbulent boundary layer. J. Fluid Mech. 804, 578607.Google Scholar
Dubief, Y. & Delcayre, F. 2000 On coherent-vortex identification in turbulence. J. Turbul. 1 (1), 011.Google Scholar
Günther, T. & Theisel, H. 2017 The state of the art in vortex extraction. In Computer Graphics Forum. Wiley Online Library.Google Scholar
Haller, G. 2005 An objective definition of a vortex. J. Fluid Mech. 525, 126.Google Scholar
Hickey, J.-P., Hussain, F. & Wu, X. 2016 Compressibility effects on the structural evolution of transitional high-speed planar wakes. J. Fluid Mech. 796, 539.Google Scholar
Hunt, J. C., Wray, A. A. & Moin, P. 1988 Eddies, streams, and convergence zones in turbulent flows. Center for Turbulence Research Report CTR-S88 193.Google Scholar
Hussain, A. K. M. F. 1986 Coherent structures and turbulence. J. Fluid Mech. 173, 303356.Google Scholar
Jeong, J. & Hussain, F. 1995 On the identification of a vortex. J. Fluid Mech. 285, 6994.Google Scholar
Jeong, J., Hussain, F., Schoppa, W. & Kim, J. 1997 Coherent structures near the wall in a turbulent channel flow. J. Fluid Mech. 332, 185214.Google Scholar
Kim, K., Hickey, J.-P. & Scalo, C.2017 Pseudophase-change effects in turbulent channel flow under transcritical temperature conditions. arXiv:1712.05777.Google Scholar
Kolář, V. 2009 Compressibility effect in vortex identification. AIAA J. 47 (2), 473475.Google Scholar
Kolář, V. & Šístek, J. 2015 Corotational and compressibility aspects leading to a modification of the vortex-identification q-criterion. AIAA J. 53 (8), 24062410.Google Scholar
Pierce, B., Moin, P. & Sayadi, T. 2013 Application of vortex identification schemes to direct numerical simulation data of a transitional boundary layer. Phys. Fluids 25 (1), 015102.Google Scholar
Pirozzoli, S., Bernardini, M. & Grasso, F. 2008 Characterization of coherent vortical structures in a supersonic turbulent boundary layer. J. Fluid Mech. 613, 205231.Google Scholar
Schoppa, W. & Hussain, F. 2002 Coherent structure generation in near-wall turbulence. J. Fluid Mech. 453, 57108.Google Scholar
Shadloo, M. S., Hadjadj, A. & Hussain, F. 2015 Statistical behavior of supersonic turbulent boundary layers with heat transfer at m = 2. Intl J. Heat Fluid Flow 53, 113134.Google Scholar
Shang, J. S., Surzhikov, S. T., Kimmel, R., Gaitonde, D., Menart, J. & Hayes, J. 2005 Mechanisms of plasma actuators for hypersonic flow control. Prog. Aerosp. Sci. 41 (8), 642668.Google Scholar
Shu, C.-W. 1998 Essentially non-oscillatory and weighted essentially non-oscillatory schemes for hyperbolic conservation laws. In Advanced Numerical Approximation of Nonlinear Hyperbolic Equations, pp. 325432. Springer.Google Scholar
Tennekes, H. & Lumley, J. L. 1972 A First Course in Turbulence. MIT Press.Google Scholar
Wu, J.-Z., Ma, H.-Y. & Zhou, M.-D. 2007 Vorticity and Vortex Dynamics. Springer Science & Business Media.Google Scholar
Zandian, A., Sirignano, W. A. & Hussain, F. 2018 Understanding liquid-jet atomization cascades via vortex dynamics. J. Fluid Mech. 843, 293354.Google Scholar
Zhang, C., Duan, L. & Choudhari, M.2016 Acoustic radiation from a mach 14 turbulent boundary layer. In 54th AIAA Aerospace Sciences Meeting, pp. 2016–0048. AIAA.Google Scholar
Zhou, J., Adrian, R. J., Balachandar, S. & Kendall, T. M. 1999 Mechanisms for generating coherent packets of hairpin vortices in channel flow. J. Fluid Mech. 387, 353396.Google Scholar