Boublik 2D hard convex body equation of state

Boublik 2D hard convex body equation of state

Helmholtz energy function (Eq. 8):

${\frac {\Delta A}{RT}}=-\ln(1-y)+{\frac {\gamma y(1+cy)}{1-y}}$

where $c$ is an unknown parameter.

Compressibility factor (Eq. 9)

$Z={\frac {1}{1-y}}+{\frac {\gamma y\left(1+2cy-cy^{2}\right)}{(1-y)^{2}}}$

For the hard disk model (Eq. 11)

$Z={\frac {1}{1-y}}+{\frac {\gamma y\left[1+\gamma \left(y/7-y^{2}/14\right)\right]}{(1-y)^{2}}}$