The present work uses the concept of a scaled particle along with the perturbation and variation approach, to develop an equation of state (EOS) for a mixture of hard sphere (HS), Lennar-Jones (L J) fluids. A su...The present work uses the concept of a scaled particle along with the perturbation and variation approach, to develop an equation of state (EOS) for a mixture of hard sphere (HS), Lennar-Jones (L J) fluids. A suitable flexible functional form for the radial distribution function G(R) is assumed for the mixture, with R as a variable. The function G(R) has an arbitrary parameter m and a different equation of state can be obtained with a suitable choice of m. For m = 0.75 and m = 0.83 results are close to molecular dynamics (MD) result for pure HS and LJ fluid respectively.展开更多
We present a simple method of obtaining various equations of state for hard sphere fluid in a simple unifying way. We will guess equations of state by using suitable axiomatic functional forms (n = 1, 2, 3, 4, 5) fo...We present a simple method of obtaining various equations of state for hard sphere fluid in a simple unifying way. We will guess equations of state by using suitable axiomatic functional forms (n = 1, 2, 3, 4, 5) for surface tension Sn (r), r≥ d/2 with intermolecular separation r as a variable, where m is an arbitrary real number (pole). Among the equations of state obtained in this way are Percus-Yevick, scaled particle theory and Carnahan-Starling equations of state. In addition, we have found a simple equation of state for the hard sphere fluid in the region that represents the simulation data accurately. It is found that for both hard sphere fluids as well as Lennard-Jones fluids, with m = 3/4 the derived equation of state (EOS) gives results which are in good agreement with computer simulation results. Furthermore, this equation of state gives the Percus-Yevick (pressure) EOS for the m = 0, the Carnahan-Starling EOS for rn = 4/5, while for the value of m = 1 it corresponds to a scaled particle theory EOS.展开更多
The molecular dynamic simulation results for the liquid-vapor interface of the pure Lennard-Jones fluid are presented. The thermodynamic properties, the surface tension and the effective thickness of interfa-cial laye...The molecular dynamic simulation results for the liquid-vapor interface of the pure Lennard-Jones fluid are presented. The thermodynamic properties, the surface tension and the effective thickness of interfa-cial layer are determined. The rough characteristic of the liquid-vapor interface is discussed with fractional Brownian motion theory. Thereupon the fractal dimension d of the liquid-vapor interface is obtained.展开更多
文摘The present work uses the concept of a scaled particle along with the perturbation and variation approach, to develop an equation of state (EOS) for a mixture of hard sphere (HS), Lennar-Jones (L J) fluids. A suitable flexible functional form for the radial distribution function G(R) is assumed for the mixture, with R as a variable. The function G(R) has an arbitrary parameter m and a different equation of state can be obtained with a suitable choice of m. For m = 0.75 and m = 0.83 results are close to molecular dynamics (MD) result for pure HS and LJ fluid respectively.
文摘We present a simple method of obtaining various equations of state for hard sphere fluid in a simple unifying way. We will guess equations of state by using suitable axiomatic functional forms (n = 1, 2, 3, 4, 5) for surface tension Sn (r), r≥ d/2 with intermolecular separation r as a variable, where m is an arbitrary real number (pole). Among the equations of state obtained in this way are Percus-Yevick, scaled particle theory and Carnahan-Starling equations of state. In addition, we have found a simple equation of state for the hard sphere fluid in the region that represents the simulation data accurately. It is found that for both hard sphere fluids as well as Lennard-Jones fluids, with m = 3/4 the derived equation of state (EOS) gives results which are in good agreement with computer simulation results. Furthermore, this equation of state gives the Percus-Yevick (pressure) EOS for the m = 0, the Carnahan-Starling EOS for rn = 4/5, while for the value of m = 1 it corresponds to a scaled particle theory EOS.
基金Funded by the National Natural Science Foundation of China( No. 50076048)
文摘The molecular dynamic simulation results for the liquid-vapor interface of the pure Lennard-Jones fluid are presented. The thermodynamic properties, the surface tension and the effective thickness of interfa-cial layer are determined. The rough characteristic of the liquid-vapor interface is discussed with fractional Brownian motion theory. Thereupon the fractal dimension d of the liquid-vapor interface is obtained.