1994 年 60 巻 573 号 p. 1683-1689
The molecular dynamics method was applied to a gas in order to clarify the mechanism of the Joule-Thomson effect, which is one of the features of real gases having intermolecular potential. In the present study, molecular motions of a monatomic gas with the Lennard-Jones potential were simulated, and the molecular behavior in equilibrium states was obtained. Comparing thermodynamic states under various conditions, the changes of temperature caused by expansion were estimated. It was found that, for the process at constant internal energy, the temperature change was attributed to the redistribution of kinetic and potential energy, while for the isenthalpic process, the temperature change occurred due to the work done by the intermolecular forces, in addition to the energy redistribution.