Programme

I.5 -- Invited, VCTP-46

Date: Monday, 4 October 2021

Time: 16:00 - 16:30

Thermodiffusion in Simple Binary Mixtures: Theoretical Models and Molecular Simulations

Hai Hoang (1), Cuong Quoc Doan (2), Han Tuong Luc (3), Guillaume Galliero (4)

(1) Institute of Fundamental and Applied Sciences, Duy Tan University, Ho Chi Minh City, Vietnam (2) Quang Binh University, Dong Hoi City, Vietnam (3) Cao Thang Technical College, Ho Chi Minh City, Vietnam (4) Universite de Pau et des Pays de l'Adour, E2S UPPA, CNRS, TOTAL, LFCR, Pau, France

Thermodiffusion is a phenomenon observed in fluid mixtures subjected to a thermal gradient, which is composition gradients of mixture constituents due to their different responses to the force of thermal gradient [1]. This phenomenon is often described by a thermal diffusion factor or Soret coefficient [2]. Accurate estimate of this quantity is highly required not only in fundamental sciences and but also in engineering applications, so many theoretical models have been developed in literature [3]. However, their limits and capabilities have not been systematically investigated, even for simple binary mixtures. This is a main goal of present work. To do so, using molecular simulations on model fluids, we have computed inputs of the available theoretical models and thermal diffusion factors of binary mixtures composed of species differing in terms of molecular parameters (molecular mass, molecular size, potential and shape), separately and then coupled, at various thermodynamic conditions [4]. It has been obtained that their predictions are rather limited even for these simple binary mixtures. In addition, we have also proposed a predictive model that is able to quantitatively compute the Sorect coefficient of the binary mixtures. [1] C. Soret (1879) Arch. Sci. Phys. Nat. 2, 46. [2] W. Köhler and K. I. Morozov (2016) J. Non-Equilib. Thermodyn. 41, 151. [3] S. Srinivasan and M. Z. Saghir (2012) - Thermodiffusion in Multicomponent Mixtures: Thermodynamic, Algebraic, and Neuro-Computing Models, Springer Science & Business Media. [4] Frenkel, D. and Smit B. (2001) Understanding molecular simulation: from algorithms to applications, Second Edition, Academic Press.

Presenter: Hoàng Hải