The Viscosity of Liquids in the Dual Model

TL;DR

This paper introduces a dual model framework for liquids that accurately predicts viscosity's temperature dependence and aligns well with experimental data, linking microscopic vibratory modes to macroscopic viscosity.

Contribution

It develops an analytical viscosity model based on dual liquid systems, incorporating vibratory degrees of freedom and fundamental constants, with validation against experimental data.

Findings

The model reproduces the Arrhenius-like temperature dependence of viscosity.

Numerical approaches based on the dual system agree with experimental viscosity values.

Viscosity expression explicitly involves sound velocity and vibratory degrees of freedom.

Abstract

A reliable model of viscosity in liquids using a dual liquid model framework is developed. The analytical expression arrived at exhibits the correct T-dependence Arrhenius-like. It is compared with the values of viscosity for water with acceptable accuracy and those related to the mechano-thermal effect in liquids under low-frequency shear. It has even been shown that a numerical approach of viscosity in liquids dealt with as dual systems provides good agreement with experimental data. The expression of viscosity shows an explicit dependence upon the sound velocity and the collective vibratory degrees of freedom excited at a given temperature. The terms involved depend upon the Boltzmann and Planck constants. Finally, the physical model is coherent with the postulate of microscopic reversibility as well as with the time's arrow for macroscopic dissipative mechanisms.