Imre A R, Mayer G, Házi G, Rozas R, Kraska T
Simulator Development Department, KFKI Atomic Energy Research Institute, Budapest, Hungary.
J Chem Phys. 2008 Mar 21;128(11):114708. doi: 10.1063/1.2837805.
Interfacial pressure and density profiles are calculated from molecular dynamics and lattice Boltzmann simulations of a liquid film in equilibrium with its vapor. The set of local values of tangential pressure and density along an interface exhibits a van der Waals-type loop; starting from the stable vapor bulk phase one passes through metastable and unstable states to the stable liquid bulk phase. The minimum and maximum values of the profile of tangential pressure are related to the liquid and vapor spinodal states, respectively. The spinodal pressures turn out to be linearly related to the extreme values of the tangential pressure in the interface. The comparison with equations of state shows good agreement with the simulation results of the spinodals. In addition the properties of the metastable region are obtained. Based on this investigation a method is proposed for the estimation of the liquid spinodal from experimentally obtained interfacial properties. Estimations for water and helium are presented.
通过对与蒸汽处于平衡状态的液膜进行分子动力学和格子玻尔兹曼模拟，计算了界面压力和密度分布。沿界面的切向压力和密度的局部值集呈现出范德瓦尔斯型回路；从稳定的气相主体开始，经过亚稳态和不稳定状态，到达稳定的液相主体。切向压力分布的最小值和最大值分别与液体和蒸汽的旋节线状态相关。结果表明，旋节线压力与界面中切向压力的极值呈线性关系。与状态方程的比较表明，与旋节线的模拟结果吻合良好。此外，还获得了亚稳区的性质。基于这项研究，提出了一种根据实验获得的界面性质估算液体旋节线的方法。给出了水和氦的估算结果。
