Weak solid–liquid interaction enhances thermal energy transport across a nanogap

Abstract

Near-field heat transfer has attracted significant attention owing to the critical role of gap scale in thermal energy transport between two objects. Our previous study verified phonon heat transfer across a nanogap via liquid layers adsorbed on the superhydrophilic surfaces. The thermal gap conductance across the nanogap is enhanced due to thermal resonance between the two liquid layers. However, it is unclear whether phonons can transmit across a nanogap under weak solid–liquid interactions. In this study, we varied the solid–liquid interaction to investigate quasi-Casimir coupling across a nanogap including the non-adsorbed atoms using non-equilibrium molecular dynamics (NEMD) simulations. The larger net heat flux of system and thermal conductance were acquired under weak solid-liquid molecular interactions owing to the contributions of solid atomic vibrations and liquid atomic collisions.

Wentao Chen

Associate Professor

My research interests include extreme near-field heat transfer, thermal transport at the solid-solid and solid-liquid interface, and molecular dynamics simulation.