References of "Lebon, Georgy"
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See detailA unified extended thermodynamic description of diffusion, thermo-diffusion, suspensions, and porous media
Lebon, Georgy ULiege; Desaive, Thomas ULiege; Dauby, Pierre ULiege

in Journal of Applied Mechanics-Transactions of the Asme (2006), 73(1), 16-20

It is shown that extended irreversible thermodynamics (EIT) provides a Unified description of a great variety of processes, including matter diffusion, thermo-diffusion, suspensions, and fluid flows in ... [more ▼]

It is shown that extended irreversible thermodynamics (EIT) provides a Unified description of a great variety of processes, including matter diffusion, thermo-diffusion, suspensions, and fluid flows in porous media. This is achieved by enlarging the set of classical variables, as mass, momentum and temperature by the corresponding fluxes of mass, momentum and heat. For simplicity, we consider only Newtonian fluids and restrict ourselves to a linear analysis: quadratic and higher order terms in the fluxes are neglected. In the case of diffusion in a binary mixture, the extra flux variable is the diffusion flux of one the constituents, say the solute. In thermo-diffusion, one adds the heat flux to the set of variables. The main result of the present approach is that the traditional equations of Fick, Fourier Soret, and Dufour are replaced by time-evolution equations for the matter and heat fluxes, such generalizations are useful in high-frequency processes. It is also shown that the analysis can be easily extended to the study of particle suspensions in fluids and to flows in porous media, when such systems can be viewed as binary mixtures with a solid and a fluid component. [less ▲]

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See detailConvection and interfacial mass exchange
Colinet, P.; Legros, Jean-Claude; Dauby, Pierre ULiege et al

in ESA Special Publication (2005, October 01)

Mass-exchange through fluid interfaces is ubiquitous in many natural and industrial processes. Yet even basic phase-change processes such as evaporation of a pure liquid are not fully understood, in ... [more ▼]

Mass-exchange through fluid interfaces is ubiquitous in many natural and industrial processes. Yet even basic phase-change processes such as evaporation of a pure liquid are not fully understood, in particular when coupled with fluid motions in the vicinity of the phase-change interface, or with microscopic physical phenomena in the vicinity of a triple line (where the interface meets a solid). Nowadays, many industries recognise that this lack of fundamental knowledge is hindering the optimisation of existing processes. Their modelling tools are too dependent on empirical correlations with a limited - and often unknown - range of applicability. In addition to the intrinsic multiscale nature of the phenomena involved in typical industrial processes linked to interfacial mass exchange, their study is highly multi-disciplinary, involving tools and techniques belonging to physical chemistry, chemical engineering, fluid dynamics, non-linear physics, non-equilibrium thermodynamics, chemistry and statistical physics. From the experimental point of view, microgravity offers a unique environment to obtain valuable data on phase-change processes, greatly reducing the influence of body forces and allowing the detailed and accurate study of interfacial dynamics. In turn, such improved understanding leads to optimisation of industrial processes and devices involving phase-change, both for space and ground applications. [less ▲]

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See detailOn an Extended Irreversible Thermodynamic description of transient heat conduction in nano structures
Lebon, Georgy ULiege; Dauby, Pierre ULiege; Grmela, M.

in Proceedings of the 2d IEEES Conference (2005, July)

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See detailBallistic-diffusive heat conduction at nanoscale: GENERIC approach [rapid communication]
Grmela, M.; Lebon, Georgy ULiege; Dauby, Pierre ULiege et al

in Physics Letters A (2005), 339

Heat conduction in nanosize systems has to be studied in settings involving microscopic details that are not seen in the classical Fourier theory. G. Chen has suggested [Phys. Rev. Lett. 86 (2001) 2297] a ... [more ▼]

Heat conduction in nanosize systems has to be studied in settings involving microscopic details that are not seen in the classical Fourier theory. G. Chen has suggested [Phys. Rev. Lett. 86 (2001) 2297] a combination of the Cattaneo setting in which the velocity of the heat propagation is finite and the kinetic theory setting in which phonons are seen as heat carriers. In this Letter we show that if the Cattaneo and the kinetic theories are combined in a way that preserves the structure expressing their compatibility with thermodynamics (GENERIC structure) then both the Cattaneo and the kinetic equations become modified. The modified Cattaneo equations involve the term introduced by Chen and, in addition, new terms that are nonlinear in quantities that disappear at equilibrium. The kinetic equation is modified by new terms involving gradients of the heat flux and the local temperature. [less ▲]

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See detailThermo-diffusion revisited: A comparative approach between two recent thermodynamic formalisms
Lebon, Georgy ULiege; Desaive, Thomas ULiege; Colinet, P.

in Journal of Non-Equilibrium thermodynamics (2004), 29(4), 405-415

Extended irreversible thermodynamics and the general equation for the non-equilibrium reversible-irreversible coupling are two thermodynamic theories that have recently received much attention, not only ... [more ▼]

Extended irreversible thermodynamics and the general equation for the non-equilibrium reversible-irreversible coupling are two thermodynamic theories that have recently received much attention, not only from the fundamental but also from the practical point of view. The objective of the present work is to compare the respective merits of these two approaches by emphasising their similarities and differences. To avoid formal and tedious developments, we have applied both formalisms to a concrete problem, namely thermo-diffusion in a binary fluid mixture of nonviscous fluids. [less ▲]

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See detailAn unified extended thermodynamic description of diffusion, thermodiffusion, suspensions and porous media
Lebon, Georgy ULiege; Desaive, Thomas ULiege; Dauby, Pierre ULiege

in Proceedings International Conference on thermal engineering theory and application, Beirut (Liban), 2004 (2004)

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See detailExtended Thermodynamic Description of Thermodiffusive Mass Transport
Lebon, Georgy ULiege; Desaive, Thomas ULiege; Dauby, Pierre ULiege et al

in Proc. 6 th Int. Meeting on Thermodiffusion (IMT6), Varenna, July 2004 (2004)

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See detailA comparative analysis of non-fickean thermodiffusion by EIT and GENERIC
Lebon, Georgy ULiege; Desaive, Thomas ULiege; Colinet, P.

in 1st international exergy, energy and environment symposium (2003)

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See detailLa thermodiffusion revisitée
Lebon, Georgy ULiege; Desaive, Thomas ULiege; Dauby, Pierre ULiege

in 6ème congrès de mécanique (2003)

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See detailThermal instability of a rotating saturated porous medium heated from below and submitted to rotation
Desaive, Thomas ULiege; Hennenberg, M.; Lebon, Georgy ULiege

in European Physical Journal B -- Condensed Matter (2002), 29(4), 641-647

In this work, we study the problem of onset of thermal convection in a rotating saturated porous medium heated from below. The effect of rotation is restricted to the Coriolis force, neglecting thus the ... [more ▼]

In this work, we study the problem of onset of thermal convection in a rotating saturated porous medium heated from below. The effect of rotation is restricted to the Coriolis force, neglecting thus the centrifugal effects, the porous medium is described by Brinkman's model. The linear eigenvalue problem is solved by means of a modified Galerkin method. The behavior of the critical temperature gradient is discussed in terms of various parameters of the system for both stationary and overstable convections. Finally a weakly nonlinear analysis is provided to derive amplitude equations and to study the onset of Kuppers-Lortz instability. [less ▲]

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See detailLinear and nonlinear thermal instability of a rotating saturated porous medium heated from below
Desaive, Thomas ULiege; Hennenberg, M.; Lebon, Georgy ULiege

in 1st international conference on applications of porous media (2002)

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See detailGeneralized Fourier equations and thermoconvective instabilities
Dauby, Pierre ULiege; Nelis, M.; Lebon, Georgy ULiege

in Revista Mexicana De Fisica (2002), 48(Suppl. 1), 57-62

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See detailCoupled capillary and gravity-driven instability in a liquid film overlying a porous layer
Desaive, Thomas ULiege; Lebon, Georgy ULiege; Hennenberg, M.

in Physical Review E (2001), 64(6, Pt 2), 66304

In this work, we study the problem of onset of thermal convection in a fluid layer overlying a porous layer, the whole system being heated from below. We use Brinkman's model to describe the porous medium ... [more ▼]

In this work, we study the problem of onset of thermal convection in a fluid layer overlying a porous layer, the whole system being heated from below. We use Brinkman's model to describe the porous medium and determine the corresponding linear stability equations. The eigenvalue problem is solved by means of a modified Galerkin method. The behavior of the critical wave number and temperature gradient is discussed in terms of the various parameters of the system. We also emphasize the influence of the boundary conditions at the upper surface of the fluid layer; in particular, we examine the role of a free surface whose surface tension is temperature dependent (Marangoni effect). Comparison with earlier works is also made. [less ▲]

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See detailRole of interface deformations in Benard-Marangoni instability
Lebon, Georgy ULiege; Dauby, Pierre ULiege; Regnier, Vincent

in Acta Astronautica (2001), 48(5-12), 617-627

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See detailLinear and nonlinear Rayleigh-Bénard-Marangoni instability with surface deformations
Regnier, Vincent; Dauby, Pierre ULiege; Lebon, Georgy ULiege

in Physics of Fluids (2000), 12

Thermoconvective instabilities in a bilayer liquid-gas system with a deformed interface are investigated. In the first part of the work which is devoted to a linear approach, emphasis is put on the role ... [more ▼]

Thermoconvective instabilities in a bilayer liquid-gas system with a deformed interface are investigated. In the first part of the work which is devoted to a linear approach, emphasis is put on the role of the upper gas layer on the instability phenomenon. The condition to be satisfied by the gas to remain purely conductive is established. The so-called Oberbeck-Boussinesq approximation is discussed and its range of validity is carefully defined. Instead of the classical Rayleigh, Marangoni, crispation, and Galileo numbers, new dimensionless groups are introduced. A critical comparison with several previous works is made. The nonlinear analysis consists in studying the different convective patterns which can appear above the threshold. Particular attention is devoted to the shape of the interface and the so-called ``hybrid'' relief. The amplitude of the deformation is also determined and comparison with experimental data is discussed. [less ▲]

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See detailSpecific topics on Bénard-Marangoni instabilities
Desaive, Thomas ULiege; Dauby, Pierre ULiege; Lebon, Georgy ULiege et al

in Henry, Daniel; Bergeon, Alain (Eds.) Proceedings of the ERCOFTAC and EUROMECH Colloquium 383 on Continuation Methods in Fluid Dynamics (2000)

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See detailCoupled capillary and gravity-driven instabilities in a bilayer porous liquid system
Desaive, Thomas ULiege; Bragard, J.; Lebon, Georgy ULiege et al

in 52nd annual meeting of the division of fluid dynamics of the American physical society (1999)

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See detailExtended Irreversible Thermodynamics Revisited ( 1988-1998)
Jou, David; Casas-Vazquez, Jose; Lebon, Georgy ULiege

in Report in progress in physics (1998), 62

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See detailLinear Benard-Marangoni instability in rigid circular containers
Dauby, Pierre ULiege; Lebon, Georgy ULiege; Bouhy, E.

in Physical Review. E : Statistical Physics, Plasmas, Fluids, and Related Interdisciplinary Topics (1997), 56(1), 520-530

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