# Multi-mode spatio-temporal instability in non-Boussinesq convection

Article

Suslov, Sergey A.. 2004. "Multi-mode spatio-temporal instability in non-Boussinesq convection." Australian and New Zealand Industrial and Applied Mathematics (ANZIAM) Journal.
Article Title Multi-mode spatio-temporal instability in non-Boussinesq convection 43 Article Suslov, Sergey A. Australian and New Zealand Industrial and Applied Mathematics (ANZIAM) Journal Australia and New Zealand Industrial and Applied Mathematics (ANZIAM) Journal 14 2004 Australia 1446-1811 1446-8735 http://anziamj.austms.org.au/V45/CTAC2003/Susl/Susl.pdf It is shown that nonlinear (non-Boussinesq) fluid property variations caused by large temperature differences between the walls of a vertical channel are responsible for the appearance of physically distinct types of instability inmixed convection flows: the previously known shear and new buoyancy-induced instabilities. Shear instability dominates the forced convection regimes, while the buoyancy instability prevails in nearly natural convection states. The most challenging situation requiring elaborate theoretical analysis and numerical verification arises in a mixed convection regime where both instabilities compete, forming a wide variety of possible flow patterns. Each of the instabilities is found to undergo the transition from a convective state (when disturbances grow and propagate away from their source) to absolute (when disturbances grow and occupy the complete flow domain). A number of regions in a complete parameter space corresponding to qualitatively different flow scenarios are identified, and accurate boundaries separating them are computed. Various patterns are illustrated by the direct evaluation of the Fourier integrals representing disturbances. non-Boussinesq convection 401207. Fundamental and theoretical fluid dynamics 401204. Computational methods in fluid flow, heat and mass transfer (incl. computational fluid dynamics) 490406. Lie groups, harmonic and Fourier analysis File reproduced in accordance with the copyright policy of the publisher/author. Department of Mathematics and Computing

https://research.usq.edu.au/item/9y333/multi-mode-spatio-temporal-instability-in-non-boussinesq-convection

###### Submitted Version
 Suslov_non-Boussinesq_convection_Author's_verision.pdf File access level: Anyone

total views
• ##### 2
views this month

## Related outputs

##### Magnetic flux density distribution in axial flux machine cores
Hewitt, Andrew, Ahfock, Tony L. and Suslov, Sergey A.. 2005. "Magnetic flux density distribution in axial flux machine cores." IET Electric Power Applications. 152 (2), pp. 192-196. https://doi.org/10.1049/ip-epa:20055039
##### Searching convective/absolute instability boundary for flows with fully numerical dispersion relation
Suslov, Sergey A.. 2001. "Searching convective/absolute instability boundary for flows with fully numerical dispersion relation." Computer Physics Communications. 142 (1-3), pp. 322-325. https://doi.org/10.1016/S0010-4655(01)00360-5
##### Convective and absolute instabilities in non-Boussinesq mixed convection
Suslov, Sergey A.. 2007. "Convective and absolute instabilities in non-Boussinesq mixed convection ." Theoretical and Computational Fluid Dynamics. 21 (4), pp. 271-290. https://doi.org/10.107/s00162-007-0049-y
##### A Petrov-Galerkin method for flows in cavities: enclosure of aspect ratio 8
Suslov, Sergey A. and Paolucci, Samuel. 2002. "A Petrov-Galerkin method for flows in cavities: enclosure of aspect ratio 8." International Journal for Numerical Methods in Fluids. 40 (8), pp. 999-1007. https://doi.org/10.1002/fld.386
##### Numerical aspects of searching convective/absolute instability transition
Suslov, Sergey A.. 2005. "Numerical aspects of searching convective/absolute instability transition." Journal of Computational Physics. 212 (1), pp. 188-217. https://doi.org/10.1016/j.jcp.2005.06.017
##### Analysis of coupling between hydrodynamic and thermal instabilities in non-Boussinesq convection
Suslov, Sergey A.. 2005. "Analysis of coupling between hydrodynamic and thermal instabilities in non-Boussinesq convection." Nonlinear Analysis Theory Methods and Applications. 63 (5-7), pp. e1435-e1443. https://doi.org/10.1016/j.na.2005.01.057
##### Magneto-hydrodynamic interaction in a vertical slot filled with ferrofluid
Bozhko, Alexandra A., Suslov, Sergey A. and Putin, Gennady F.. 2008. "Magneto-hydrodynamic interaction in a vertical slot filled with ferrofluid." Alemany, A., Chopart, Jean-Paul and Freibergs, J. (ed.) 7th PAMIR International Conference on Fundamental and Applied MHD. Giens Peninsula, France 08 - 12 Sep 2008 Grenoble, France.
##### Stability of plane Poiseuille flow of a fluid with pressure-dependent viscosity
Tran, Thien Duc and Suslov, Sergey A.. 2008. "Stability of plane Poiseuille flow of a fluid with pressure-dependent viscosity ." Denier, J., Finn, M. D. and Mattner, T. (ed.) 22nd International Congress of Theoretical and Applied Mechanics ICTAM 2008. Adelaide, Australia 24 - 29 Aug 2008 Adelaide, Australia.
##### Thermo-magneto-convective instabilities in a vertical layer of ferro-magnetic fluid
Suslov, Sergey A., Bozhko, Alexandra A. and Putin, Gennady F.. 2008. "Thermo-magneto-convective instabilities in a vertical layer of ferro-magnetic fluid." Indeitsev, Dmitry A. (ed.) 36th International Conference Advanced Problems in Mechanics. Repino, Russia 06 - 10 Jul 2008 St Petersburg, Russia.
##### Stability of plane Poiseuille-Couette flows of a piezo-viscous fluid
Tran, Thien Duc and Suslov, Sergey A.. 2009. "Stability of plane Poiseuille-Couette flows of a piezo-viscous fluid." Journal of Non-Newtonian Fluid Mechanics. 156 (3), pp. 139-149. https://doi.org/10.1016/j.jnnfm.2008.07.009
##### Analysis of instability patterns in non-Boussinesq mixed convection using a direct numerical evaluation of disturbance integrals
Suslov, Sergey A.. 2009. "Analysis of instability patterns in non-Boussinesq mixed convection using a direct numerical evaluation of disturbance integrals." Computers and Fluids. 38 (3), pp. 590-601. https://doi.org/10.1016/j.compfluid.2008.06.002
##### Advection-dispersion in symmetric field-flow fractionation channels
Suslov, Sergey A. and Roberts, A. J.. 1998. Advection-dispersion in symmetric field-flow fractionation channels. Toowoomba, Australia. University of Southern Queensland.
##### Bifurcations in convection of incompressible fluid in a rotated square cylinder
Sharifulin, Albert and Suslov, Sergey A.. 2008. "Bifurcations in convection of incompressible fluid in a rotated square cylinder." Denier, J., Finn, M. D. and Mattner, T. (ed.) 22nd International Congress of Theoretical and Applied Mechanics ICTAM 2008. Adelaide, Australia 24 - 29 Aug 2008 Adelaide, Australia.
##### Revisiting plane Couette-Poiseuille flows of a piezo-viscous fluid
Suslov, Sergey A. and Tran, Thien Duc. 2008. "Revisiting plane Couette-Poiseuille flows of a piezo-viscous fluid." Journal of Non-Newtonian Fluid Mechanics. 154 (2-3), pp. 170-178. https://doi.org/10.1016/j.jnnfm.2008.04.010.
##### Thermo-magnetic convection in a vertical layer of ferromagnetic fluid
Suslov, Sergey A.. 2008. "Thermo-magnetic convection in a vertical layer of ferromagnetic fluid." Physics of Fluids. 20 (8), pp. 084101-084118. https://doi.org/10.1063/1.2952596
##### Phenomenological approach to 3D spinning combustion waves: numerical experiments with a rectangular rod
Strunin, Dmitry V. and Suslov, Sergey A.. 2005. "Phenomenological approach to 3D spinning combustion waves: numerical experiments with a rectangular rod." International Journal of Self Propagating High Temperature Synthesis. 14 (1), pp. 33-39.
##### New spatio-temporal instability scenarios in non-Boussinesq mixed convection
Suslov, Sergey A.. 2007. "New spatio-temporal instability scenarios in non-Boussinesq mixed convection." Sathyasheelappa, Vinaya K. (ed.) 60th Annual Meeting of the Divison of Fluid Dynamics, American Physical Society. Salt Lake City, United States 18 - 20 Nov 2007 College Park, MD.
##### Two-equation model of mean flow resonances in subcritical flow systems
Suslov, S. A.. 2008. "Two-equation model of mean flow resonances in subcritical flow systems." Discrete and Continuous Dynamical Systems Series S, Selected Topics. 1 (1), pp. 165-176.
##### Spatio-temporal instabilities in mixed convection of air subject to large temperature gradient
Suslov, Sergey A.. 2004. "Spatio-temporal instabilities in mixed convection of air subject to large temperature gradient ." Lyubimov, Dmitry V. (ed.) International Conference: Advanced Problems in Thermal Convection (2004). Perm, Russia 24 - 27 Nov 2003 Perm, Russia.
##### Flow patterns near codimension-2 bifurcation in non-Boussinesq mixed convection
Suslov, Sergey A.. 2002. "Flow patterns near codimension-2 bifurcation in non-Boussinesq mixed convection ." Shalfeev, V. D. (ed.) Progress in Nonlinear Science, International Conference dedicated to the 100th Anniversary of A.A. Andronov. Nizhniy Novgorod, Russia 02 - 06 Jul 2001 Nizniy Novgorod, Russia.
##### Effect of fluid properties variations on spatio-temporal instability of convection
Suslov, Sergey A.. 2002. "Effect of fluid properties variations on spatio-temporal instability of convection." Indeitsev, Dmitry A. (ed.) APM 2001: 29th Summer School on 'Advanced Problems in Mechanics. Repino, Russia 21 - 30 Jun 2001 St. Petersburg, Russia.
##### Stability of non-Boussinesq convection via the complex Ginzburg-Landau model
Suslov, Sergey A. and Paolucci, Samuel. 2004. "Stability of non-Boussinesq convection via the complex Ginzburg-Landau model." Fluid Dynamics Research. 35 (3), pp. 159-203. https://doi.org/10.1016/j.fluiddyn.2004.06.002