Next Article in Journal
Maximising Reproduction under Extensive Grazing Conditions, Regardless of Rainfall
Previous Article in Journal
Multi-Disciplinary Interventions for Children and Adolescents with Obesity: the Whānau Pakari Experience
Open AccessProceedings

Comparative Examination of Nonequilibrium Thermodynamic Models of Thermodiffusion in Liquids

Institute of Biochemical Physics RAS, Moscow 119334, Russia
Department of Chemistry, Boise State University, Boise, ID 83725, USA
Author to whom correspondence should be addressed.
Presented at the 5th International Electronic Conference on Entropy and Its Applications, 18–30 November 2019; Available online:
Proceedings 2020, 46(1), 14;
Published: 17 November 2019
We analyze existing models for material transport in non-isothermal non-electrolyte liquid mixtures that utilize non-equilibrium thermodynamics. Many different sets of equations for material have been derived that, while based on the same fundamental expression of entropy production, utilize different terms of the temperature- and concentration-induced gradients in the chemical potential to express the material flux. We reason that only by establishing a system of transport equations that satisfies the following three requirements can we obtain a valid thermodynamic model of thermodiffusion based on entropy production, and understand the underlying physical mechanism: (1) Maintenance of mechanical equilibrium in a closed steady-state system, expressed by a form of the Gibbs–Duhem equation that accounts for all the relevant gradients in concentration, temperature, and pressure and respective thermodynamic forces; (2) thermodiffusion (thermophoresis) is zero in pure unbounded liquids (i.e., in the absence of wall effects); (3) invariance in the derived concentrations of components in a mixture, regardless of which concentration or material flux is considered to be the dependent versus independent variable in an overdetermined system of material transport equations. The analysis shows that thermodiffusion in liquids is based on the entropic mechanism.
Keywords: thermodiffusion; thermophoresis; non-equilibrium thermodynamics thermodiffusion; thermophoresis; non-equilibrium thermodynamics
MDPI and ACS Style

Semenov, S.N.; Schimpf, M.E. Comparative Examination of Nonequilibrium Thermodynamic Models of Thermodiffusion in Liquids. Proceedings 2020, 46, 14.

Show more citation formats Show less citations formats
Note that from the first issue of 2016, MDPI journals use article numbers instead of page numbers. See further details here.

Article Access Map by Country/Region

Back to TopTop