Equations of state for hard-sphere fluids
Equations of state and contact values of hard-sphere radial distribution functions (rdf's) which are given by a linear combination of the Percus-Yevick and scaled-particle virial expressions are considered. In the one-component case the mixing coefficient /theta/(/eta/)is, in general a function of the volume fraction /eta/. In mixtures the coefficient /theta/(/eta//sub i/, d/sub i/), in general, depends upon the volume fraction /eta//sub i/ and diameter d/sub i/ of each species, i and j. For the contact values Y/sub ij/ of the rdf's, the mixing coefficients /Theta//sub ij/(/eta//sub k/) also depend on species i and j. Density expansions for the exact /theta/ for the one-component hard-sphere fluid are obtained and compared with several approximations made in earlier works and in the authors own work, as well as with simulation. For a mixture, it turns out that one cannot obtain the exact fourth virial coefficient by using a linear combination of the Percus-Yevick and scaled-particle virial expression for Y/sub ij/ unless one allows /Theta//sub ij/ to depend on mole fractions x/sub i/ even at the zeroth order of its density expansion. They also find that /Theta//sub ij/ must depend on particle species i and j in order to satisfy the exact limits obtained earlier by Sung and Stell. A new equation of state for the binary hard-sphere mixture which satisfies all the exact limits they have considered is suggested.
- Research Organization:
- State Univ. of New York, Stony Brook (USA)
- OSTI ID:
- 5844036
- Report Number(s):
- CONF-880606-
- Journal Information:
- Int. J. Thermophys.; (United States), Vol. 9:6; Conference: 10. symposium on thermophysical properties, Gaithersburg, MD, USA, 20-23 Jun 1988
- Country of Publication:
- United States
- Language:
- English
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