Hydrodynamic anomalies in supercritical fluid

R. E. Ryltsev; N. M. Chtchelkatchev

doi:10.1063/1.4895726

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arXiv · 1407.5462

Hydrodynamic anomalies in supercritical fluid

R. E. Ryltsev·N. M. Chtchelkatchev

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Abstract

Using the molecular dynamics simulations we investigate properties of velocity autocorrelation function of Lennard-Jones fluid at long and intermediate time scales in wide ranges of temperature and density. We show that the amplitudes of the leading and subleading VAF time asymptotes, $a_1$ and $a_2$, show essentially non monotonous temperature and density dependence. There are two lines on temperature-density plain corresponding to maxima of $a_1$ ($a_2$) along isochors and isotherms situated in the supercritical fluid (hydrodynamic anomalies). These lines give insight into the stages of the fluid evolution into gas.

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R. E. Ryltsev, N. M. Chtchelkatchev. 2014-08-07. Hydrodynamic anomalies in supercritical fluid. https://doi.org/10.1063/1.4895726

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