Elementary Research on the Dispersion and Stability of Nanofluids by Molecular Dynamics Simulations

The preparation and dispersionstability of nanofluids are basic work for follow-up research.In this paper,equilibrium molecular dynamics is used to investigate the dispersionstability of nanofluids with solid copper nanoparticles dispersed into the fluid CO_2.By tracking the position of the solid and fluid molecule,the fluid layer around the nanoparticle and nanoparticle aggregation are both investigated.They are also investigated by changing the attractive force and the repulsive force between solid and fluid molecule.The results show that a layer of fluid is formed around nanoparticle. More fluid molecules are attracted to form the layer around the nanoparticle when the attractive force between solid and fluid is increased,but the thickness of the fluid layer does not change.Nanoparticle aggregation is also controlled or delayed when the attractive force between solid and fluid is increased, which provides a new train of thought for nanoparticles dispersing into the fluid.