Comparison of the scaling models for substance densities along saturation line

31st International Conference on Equations of State for Matter

Vorob'Yev, V.S.^1 ; Rykov, V.A.^2 ; Ustyuzhanin, E.E.^3 ; Shishakov, V.V.^3 ; Popov, P.V.^3 ; Rykov, S.V.^2

Joint Institute for High Temperatures of the Russian Academy of Sciences, Izhorskaya 13, Moscow

125412, Russia^1

ITMO University, Kronvergskiy 49, Saint-Petersburg

197101, Russia^2

National Research University Moscow Power Engineering Institute, Krasnokazarmennaya 14, Moscow

111250, Russia^3

关键词: Critical exponent;    Critical region;    Critical temperatures;    Order parameter;    Saturation line;    Scaling equations;    Scaling functions;    Thermodynamic equations;   

Others  :  https://iopscience.iop.org/article/10.1088/1742-6596/774/1/012017/pdf
DOI  :  10.1088/1742-6596/774/1/012017

来源: IOP

【 摘 要 】

We discuss various thermodynamic equations used to represent the properties along the saturation line (fluid density, gas density, order parameter, mean diameter, etc) in a neighborhood of the critical temperature Tc. These properties are described scaling functions, depending on some parameters including the critical exponents α and β. Along with well-known models, we investigate a new model that represents the mean diameter as a sum of two scaling members in the critical region. The first term of this sum depends on the exponent, a and the second one depends on exponent, 2β. In the paper is given a methodological rationale for the new function representing the mean diameter. We have made numerical estimates for sulphur hexafluoride using the parameters involving with the above scaling equations.