低温下液氦、液氖热物性的分子动力学模拟

Numerical Simulation of the Thermophysical Properties of Liquid He and Liquid Ne at Low Temperature

本文基于平衡分子动力学模拟方法,采用了含量子修正项的QFH势函数和WK势函数对低温下液氦和液氖进行计算,并通过Green-Kubo公式统计得到热导率和黏性系数。结果表明:液氦和液氖的热导率、黏性系数随温度升高呈线性增大;采用QFH势函数和WK势函数比采用LJ势函数计算得到的热导率更接近实验值,且WK势函数计算结果比采用QFH势获得的结果更准确;WK势函数计算的液氦和液氖的黏性系数也与实验值非常接近。

Based on the equilibrium molecular dynamics method, the thermophysical properties of liquid He and liquid Ne at low temperature are calculated by using the QFH and WK poten- tial function including quantum correction items. The thermal conductivities and viscosities are then obtained through the Green-Kubo equation. The results show that they increase linearly with the temperature and closer to the experimental data by using the QFH and WK potential function than using the LJ potential function. Furthermore, the calculated thermal conductivities are more accurate by using the WK potential than using the QFH potential. The viscosities of the liquid He and liquid Ne by using the WK potential function are very close to the experimental data.