【摘要】 为了研究尺寸变化对纳米颗粒导热的影响,采用非平衡分子动力学模拟方法研究了固定原子壁面边界条件下,平均温度在45K、边长为3.186~12.744 nm的立方形和半径为4.248~10.62 nm的球形2种纳米Ar颗粒的热导率,并与其他研究者的结果及薄膜的模拟值进行了对比。模拟结果表明,在固壁边界条件下,2种颗粒的热导率均随着尺寸的增加而趋向块体值,但均小于相同厚度、相同边界条件的Ar薄膜的热导率;球形颗粒的热导率小于边长与其半径相等的立方形颗粒的热导率。更多还原

【Abstract】 Non-equilibrium molecular dynamics simulations were performed to investigate nanoparticle thermal conductivity variations with particle size.The thermal conductivities of cubic and spherical argon nanoparticles with fixed atom boundaries were simulated at 45 K in cubes having sides of 3.186-12.744 nm and in spheres having radii of 4.248-10.62 nm.The results show that the thermal conductivities of the two types of particles both increase with size and approach the bulk material,but the thermal conductivities of all these particles are smaller than that of an argon thin film with the same thickness and same boundary conditions.The thermal conductivities of spherical particles are smaller than those of cubic particles when the spherical particle radii are equal to lengths of sides of the cubic particles.更多还原