Simulaciones de dinámica molecular de conductividad térmica entre dos nanopartículas en contacto

Abstract

The nanoscale properties of materials can have a great influence on their macroscopic behavior; for instance, the generation and accumulationof defects at the nanoscale, such as point defects, porosity, and interfaces, can change their thermal properties. In this work, we studythe role of an interface in the thermal conductivity between two nanoparticles without any external load. We consider a system subjected toa temperature gradient perpendicular to the contact surface and study the thermal conductivity, thermal conductance, thermal resistance,and contact resistance vs nanoparticle size. The thermal resistance at the interface increases linearly with nanoparticles? contact radius ac.A model based on the contact area between two nanoparticles allows us to reasonably explain the obtained numerical results for thethermal conductivity, leading to a net decrease in effective conductivity as the nanoparticle size increases, reasonably well described by a(ac/R) dependence. Simulated thermal conductance was found to be proportional to (ac/R).