Thermal fluctuations in metastable fluids
نویسندگان
چکیده
In this work, the thermal fluctuations of fluid in metastable conditions have been theoretically investigated. The is described with a diffuse interface approach based on Van der Waals squared-gradient theory (SGT), where free energy augmented by density square gradient term to take into account capillary effects. By averaging physical observables coarse-graining cells, it found that capillarity strongly modifies fluctuation statistics when increasing metastability. A remarkable difference respect simple description also detected approaching nanoscopic scales. Peculiarly, near spinodal loci, classical envisages divergent behavior intensity, while SGT provides finite variance field. scaling lines analytically derived and discussed. Finally, correlation length system identified for different metastabilities. Also latter case, critical exponents are calculated. theoretical results corroborated Landau–Lifshitz–Navier–Stokes fluctuating hydrodynamics simulations.
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ژورنال
عنوان ژورنال: Physics of Fluids
سال: 2022
ISSN: ['1527-2435', '1089-7666', '1070-6631']
DOI: https://doi.org/10.1063/5.0132478