Non-equilibrium fluctuations induced by the Soret effect in a ternary mixture

Impact of Thermodiffusion on the Initial Vertical Distribution of Species in Hydrocarbon Reservoirs

“…-ground experiments (Croccolo et al 2012;Urteaga et al 2012;Giraudet et al 2014;Larrañaga et al 2015) on thermodiffusion in ternary mixtures that will take advantage of an extension of the theory of nonequilibrium fluctuations in ternary mixtures (Ortiz de Zárate et al 2014), -Molecular Dynamics (MD) simulations of thermodiffusion in multicomponent mixtures in bulk (Galliero et al 2003;Galliero et al 2009;Artola and Rousseau 2013) and confined situations (Galliero et al 2006;Hannaoui et al 2013), -developing models to take into account thermodiffusion when describing the initial state of a reservoir (Montel et al 2007;Touzet et al 2011).…”

Gravity effects on Soret-induced non-equilibrium fluctuations in ternary mixtures

“…As previous investigations in binary mixtures have shown [23], gravity has no influence in the spatial spectrum of NE fluctuations for large wave numbers q → ∞ so that, in addition to microgravity conditions, the results of ref. [31] are applicable to ground conditions as an asymptotic limit, as experimentally verified by Bataller et al [32].…”

“…To simplify the problem, as elucidated by other researchers in the field [4,37] and by us in previous publications [30,31], it is convenient to adopt a series of approximations, adequate for ternary liquid mixtures, before attempting any detailed calculation. Here, we shall consider the same approximations used in our previous publications [30,31], to which we refer for a detailed discussion. In summary, they amount to incompressible (divergence-free) flow, large values of the Lewis and the Schmidt numbers and use of average thermophysical properties.…”

“…In the case of multi-component systems large Lewis and Schmidt numbers means that both thermal diffusivity a and kinematic viscosity ν of the mixture are much larger than all eigenvalues of the diffusion matrix [4]. Under these simplifications, fluctuations in the concentrations (δc 1 and δc 2 for a ternary mixture) are only coupled with fluctuations in the fluid velocity component parallel to the gradients (δv z ), explicitly reading [31] …”

“…As a second step [31], we evaluated in the absence of gravity the spectrum of thermodynamic fluctuations when a ternary mixture is subjected to a stationary temperature gradient, so that a composition gradient is induced by the Soret effect. As previous investigations in binary mixtures have shown [23], gravity has no influence in the spatial spectrum of NE fluctuations for large wave numbers q → ∞ so that, in addition to microgravity conditions, the results of ref.…”