温度对Lennard-Jones流体凝结过程影响的研究

采用平衡态分子动力学模拟方法，对由氩分子构成的气液界面系统进行了较大温度跨度条件下的模拟和研究．通过统计的方法得到了温度变化对系统的密度、气液界面厚度、气态分子碰撞流率、Lennard-Jones（L-J）势能以及L-J势能力分布的影响规律．结果表明：随着温度的升高，气液界面厚度和气态分子碰撞流率增加，密度和L-J势能分布趋于均匀化，L-J势能力分布随着势阱深度的减小而趋于0；所有物理量在接近临界温度时变化加快．模拟得到不同温度条件下的凝结系数与文献相互吻合．同时，对于凝结系数随温度的升高而减小，并在温度接近临界温度时由于气液界面的消失而失去意义这一规律，通过气液界面厚度与气态分子碰撞流率随温度的增加所产生的综合效果进行了合理的解释．

Influence of Temperature on Condensation Process of Lennard-Jones Fluid

Equilibrium molecular dynamics simulations were carried out in this research to study the dynamics of the interface system composed of argon molecules at the temperatures from 83.5K to 170K.The temperature dependences density,the thickness of interface,the collision flux,the Lennard-Jones(L-J) potential energy and L-J potential force were obtained statistically and analyzed.The results show that when the temperature rises,the thickness of interface and the collision flux increase,the density and the LJ potential distribution tend to be uniform and the L-J potential force distribution inclines to zero with the decrease of the depth of the potential well.All the values change sharply when the system is close to the critical state.The condensation coefficients at different temperatures obtained from this study agree with those from other authors.In addition,the statistical results show that the condensation coefficient decreases with the increase of temperature until the interface disappears when approaching critical temperature.This phenomenon can be well explained by the interaction between the thickness of interface and the collision flux when the temperature rises.