초록 |
Among several categories of equation of state, the hard-sphere equation of state is adapted as a very useful reference system to represent numerous types of molecular fluids despite of its simplicity. Further, the hard-sphere system has another merit that it can be extended directly to the hard-sphere-chain system by introducing chain connectivity term, which is used in most existing equations of state for chain-like molecules. In this study, we developed three hard-sphere-chain equations of state based on the well-known Carnahan-Starling hard-sphere equation differing in the perturbation terms, that have more simplified form than those of the models mentioned above. Each model is directly extended from the Carnahan-Starling equation by introducing a bonding term which accounts for the chain connectivity. We then compared each model with computer simulation data and experimental vapor-liquid equilibrium data of pure saturated fluids. |