中文摘要：

采用非平衡态分子动力学方法,模拟计算了多层石墨烯之间和硅薄膜之间的接触热导随薄膜厚度增长的变化趋势.模拟结果显示,多层石墨烯之间的接触热导在厚度方向有显著的尺寸效应,随着厚度的增大,接触热导显著增大,而硅薄膜之间的接触热导随着厚度的增大没有明显变化.另外,根据声子辐射理论,采用各向异性的Debye模型,定义了接触热导尺寸效应强度α,并计算了尺寸效应强度随薄膜厚度增长的变化趋势.结果显示,声子聚焦效应对薄膜间接触热导的尺寸效应有很大影响.该结论有助于建立薄膜之间的接触热导模型和调控纳米复合材料的传热学性质.

英文摘要：

Thickness-dependent contact thermal conductance （CTC） between multilayer graphene as well as silicon thin films was investigated using the nonequilibrium molecular dynamics simulation method. The simulation results show that the CTC between multilayer graphenes is thickness dependent, and increases as the thickness gets larger. However, the CTC between silicon thin films is almost thickness independent. In addition, according to the phonon irradiation theory and the anisotropic Debye model, size effect strength a was defined and was calculated to show its variation trend as the film thickness increases. The results show that the phonon focusing dose plays an important role in the thickness dependence of CTC. This conclusion is helpful in establishing the model of CTC between thin films and in controlling the engineering thermal transport properties of nanocomposites.