Lattice Boltzmann modeling of interfacial mass transfer: Mass accommodation coefficient in liquid–vapor phase change

Abstract

The Schrage equation has been extensively used to calculate the interfacial heat/mass transfer rate during liquid–vapor phase change processes including boiling, evaporation and condensation. A critical parameter in this equation is the mass accommodation coefficient (MAC). We demonstrate that as device miniaturization progresses, the interfacial evaporation thermal resistance becomes increasingly significant, making MAC a key factor in determining the overall heat transfer performance. Using a mesoscopic approach for nano−/microscale liquid–vapor phase change heat transfer, we determine MAC values for pentane, water and hydrofluoroether-7100 (HFE-7100) under diverse conditions. Our results demonstrate a remarkable consistency between MAC values obtained from temperature-driven and pressure-driven phase transitions, indicating that the MAC is unaffected by the phase change driving forces. Furthermore, we show that while disjoining pressure suppresses evaporation by reducing the equilibrium vapor pressure, it has no discernible effect on the MAC value itself. Based on MAC values determined by our approach, we predict heat transfer performance of the porous wick and identify the optimal porosity that maximizes the overall heat transfer coefficient. This study provides an effective tool for predicting the MAC and interfacial transport rates in various liquid–vapor phase change phenomena, which are widely used in thermal management of high-heat-flux electronics.