基于分子动力学研究纳米薄膜的导热系数现状,建立了一种导热模型.采用非平衡态分子动力学研究了纳米薄膜长度、厚度、空穴对导热系数的影响.选取结构简单、可靠实验数据和势能函数的晶体氩为模型,计算了氩晶体薄膜面向导热系数,模拟结果表明:纳米薄膜面向导热系数随薄膜长度和厚度增加而增加,增加到一定尺寸时,不再增加,近似相等,具有显著的尺寸效应,相同条件下,存在空穴的氩晶体纳米薄膜导热系数低于理想氩晶体纳米薄膜的导热系数.
We eatablish a heat conduction model to investigate the thermal conductivity of nano-films based on moleculer dynamics simulations. The present work uses non-equilibrium moleculer dynamics to study the effects of length , thickness and cavity on the thermal conductivity. We present calculations of the thermal conductivity of the argon films in the direction along the planes using simple structure, stable data and the potential energy of argon crystal. Simulation results show that the thermal conductivity of the argon films in the direction along the planes increase with the increase of length and thickness when they increase to a dimension,which are equal to numerical value. The size-effect is significant. The thermal conductivity of the argon films in the direction along the planes is more higher than the thermal conductivity which possess cavities under the same condition.