Effects of roughness and radius of nanoparticles on the condensation of nanofluid structures with molecular dynamics simulation: Statistical approach

Background: M.D. simulation is a kind of computational branch of physics. In this method, the interaction between particles at intervals of time according to physics laws is simulated by a computer. Methods: In this computational study, metallic nanoparticles' effect in a phase transition of atomic fluid is described. In this research, the molecular dynamics (M.D.) method was used by Argon (Ar) atoms simulations as base fluid and copper (Cu) structure as nanoparticles between Platinum (Pt) walls. Further, the atomic barrier with cubic and rectangular shapes in simulated walls was intended for more atomic analysis of fluid/nanofluid. Some parameters such as potential energy, temperature, and thermal conductivity were reported for the atomic behavior description of defined structures. Also, in this study, change the number of roughness and changes in the radius of copper nanoparticles in the simulation structure were investigated. Significant findings: The MD results show that simulated structures reach to equilibration phase after 2000000-time steps. Further, the heat flux increases by atomic barrier inserting into Pt walls. As a result, more fluid particles show the phase phenomenon in the M.D. box. Also, the addition of Cu nanoparticles to the Ar fluid shows a similar result in which these nanoparticles improve the base fluid's thermal behavior. Finally, the number of condensed argon fluid particles into the liquid phase increases from 3221 to 3347 particles. © 2021 Taiwan Institute of Chemical Engineers