Phase Transitions of Fluids in Heterogeneous Pores.

Kód výsledku v IS VaVaI

<a href="https://www.isvavai.cz/riv?ss=detail&h=RIV%2F67985858%3A_____%2F16%3A00466473" target="_blank" >RIV/67985858:_____/16:00466473 - isvavai.cz</a>

Výsledek na webu

<a href="http://dx.doi.org/10.5488/CMP.19.13604" target="_blank" >http://dx.doi.org/10.5488/CMP.19.13604</a>

DOI - Digital Object Identifier

<a href="http://dx.doi.org/10.5488/CMP.19.13604" target="_blank" >10.5488/CMP.19.13604</a>

Jazyk výsledku

angličtina

Název v původním jazyce

Phase Transitions of Fluids in Heterogeneous Pores.

Popis výsledku v původním jazyce

We study phase behaviour of a model fluid confined between two unlike parallel walls in the presence of long range (dispersion) forces. Predictions obtained from macroscopic (geometric) and mesoscopic arguments are compared with numerical solutions of a non-local density functional theory. Two capillary models are considered. For a capillary comprising of two (differently) adsorbing walls we show that simple geometric arguments lead to the generalized Kelvin equation locating capillary condensation very accurately, provided both walls are only partially wet. If at least one of the walls is in complete wetting regime, the Kelvin equation should be modified by capturing the effect of thick wetting films by including Derjaguin's correction. Within the second model, we consider a capillary formed of two competing walls, so that one tends to be wet and the other dry. In this case, an interface localized-delocalized transition occurs at bulk two-phase coexistence and a temperature T* (L) depending on the pore width L. A mean-field analysis shows that for walls exhibiting first-order wetting transition at a temperature T-w, T-s > T* (L) > T-w, where the spinodal temperature T-s can be associated with the prewetting critical point, which also determines a critical pore width below which the interface localized-delocalized transition does not occur. If the walls exhibit critical wetting, the transition is shifted below Tw and for a model with the binding potential W(T)= A(T)l(-2) + B(T)l(-3) + ... , where L is the location of the liquid gas interface, the transition can be characterized by a dimensionless parameter kappa = B I (AL), so that the fluid configuration with delocalized interface is stable in the interval between kappa = -2/3 and kappa approximate to -0.23.

Název v anglickém jazyce

Phase Transitions of Fluids in Heterogeneous Pores.

Popis výsledku anglicky

We study phase behaviour of a model fluid confined between two unlike parallel walls in the presence of long range (dispersion) forces. Predictions obtained from macroscopic (geometric) and mesoscopic arguments are compared with numerical solutions of a non-local density functional theory. Two capillary models are considered. For a capillary comprising of two (differently) adsorbing walls we show that simple geometric arguments lead to the generalized Kelvin equation locating capillary condensation very accurately, provided both walls are only partially wet. If at least one of the walls is in complete wetting regime, the Kelvin equation should be modified by capturing the effect of thick wetting films by including Derjaguin's correction. Within the second model, we consider a capillary formed of two competing walls, so that one tends to be wet and the other dry. In this case, an interface localized-delocalized transition occurs at bulk two-phase coexistence and a temperature T* (L) depending on the pore width L. A mean-field analysis shows that for walls exhibiting first-order wetting transition at a temperature T-w, T-s > T* (L) > T-w, where the spinodal temperature T-s can be associated with the prewetting critical point, which also determines a critical pore width below which the interface localized-delocalized transition does not occur. If the walls exhibit critical wetting, the transition is shifted below Tw and for a model with the binding potential W(T)= A(T)l(-2) + B(T)l(-3) + ... , where L is the location of the liquid gas interface, the transition can be characterized by a dimensionless parameter kappa = B I (AL), so that the fluid configuration with delocalized interface is stable in the interval between kappa = -2/3 and kappa approximate to -0.23.

Druh

J_x - Nezařazeno - Článek v odborném periodiku (Jimp, Jsc a Jost)

CEP obor

CF - Fyzikální chemie a teoretická chemie

OECD FORD obor

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Projekt

<a href="/cs/project/GA13-09914S" target="_blank" >GA13-09914S: Studium difuzních procesů v porézních látkách s proměnnou propustností</a><br>

Návaznosti

I - Institucionalni podpora na dlouhodoby koncepcni rozvoj vyzkumne organizace

Rok uplatnění

2016

Kód důvěrnosti údajů

S - Úplné a pravdivé údaje o projektu nepodléhají ochraně podle zvláštních právních předpisů

Název periodika

Condensed Matter Physics

ISSN

1607-324X

e-ISSN

—

Svazek periodika

19

Číslo periodika v rámci svazku

1

Stát vydavatele periodika

UA - Ukrajina

Počet stran výsledku

18

Strana od-do

—

Kód UT WoS článku

000373129400010

EID výsledku v databázi Scopus

2-s2.0-84959468914