The 10th Asian Symposium on Computational Heat Transfer and Fluid Flow ( ASCHT2025)

Accurate simulation of evaporation is vital for engineering applications, yet traditional methods face limitations. Molecular Dynamic (MD) offers high accuracy but is computationally intensive, while the S-model Boltzmann Kinetic Equation (SBKE) efficiently models rarefied gas flows but lacks robust surface boundary condition. To overcome these challenges, we propose a novel hybrid MD-SBKE method for nano/micro-scale evaporation.  MD simulates the liquid phase and interface, while SBKE handles the vapor region, bridging microscopic and mesoscopic scales. This approach addresses the critical challenge of mass transfer between regimes during evaporation. Validated through numerical experiments, our one-dimensional hybrid model simulates argon nanoscale thin-film evaporation in parallel plate geometry. Results demonstrate improved accuracy over pure SBKE and significant computational efficiency gains versus pure MD, enabling reliable evaporation modeling at reduced cost.

Evaporation,Hybrid,Interface,Liquid phase,Molecular Dynamic,Coupling