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Updated: Oct 19, 2025

An Analog Macroscopic Technique for Studying Molecular Hydrodynamic Processes in Dense Gases and Liquids
Published on: December 4, 2017
Modification of the Nonanalytic Equation of State for the Limit of Low Densities
1Institute for Basic Standards, National Bureau of Standards, Boulder, Colorado 80302.
Abstract:
As described in previous reports, this equation is constrained to the liquid-vapor coexistence boundary. Integration of the "thermodynamic equation of state" along isotherms involves a term for the compressibility factor of saturated vapor in the limit of low densities, which in previous work was not adequately defined. The present, brief report assumes familiarity with previous work, and presents a solution for the problem, which is to describe saturated-vapor densities in terms of the compressibility factor for saturated vapor, utilizing a given, vapor-pressure equation.
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