Light-induced latent heat reduction of silver nanofluids: A molecular dynamics simulation

Abstract

In recent years, some researches have revealed the addition of nanoparticles into base fluids can not only enhance the absorption of solar energy but also have an obvious influence on the latent heat of vaporization (LHV). In present work, a calculation model is developed based on the combination of molecular dynamics (MD) simulation and the electromagnetic theory to study the influence of the localized surface plasmon resonance (LSPR) effect on the LHV of silver nanofluids in the light-induced distillation process. The results show the LHV of silver nanofluids is slightly higher than that of pure water without the LSPR effect, and the water molecules are completely absorbed on the surface of silver nanoparticles due to the attraction force. However, under the effect of LSPR, the LHV of silver nanofluids is decreased with the increasing intensity of the local enhanced electric field on the surface of the silver nanoparticle. When the intensity reaches 3.0 × 1010 V/m, the LHV of silver nanofluids is reduced by 65.84% relative to that of pure water. Both of the kinetic energy and potential energy of water molecules under the local enhanced electric field induced by the LSPR are also increased with the intensity of electric field, which leads to a state conversion of water molecules from an inactive state to an active state. The required energy for water molecules from a liquid state to a vapor state is reduced under the illumination of the resonant light. Hence, the LSPR effect of nanoparticles is a significant influence in the enhanced distillation of the plasmon nanofluids.