Heterogeneous multiscale modelling of dodecane drop vaporization in nitrogen

Understanding vaporization and mixing of hydrocarbon fuels under supercritical conditions is crucial for designing rocket engines and gas turbines. The challenging task is to accurately study the liquid-vapor interface, which is of molecular thickness, while also accounting for the mass, momentum and energy transfer at a macroscopic scale. Computational models rely on macroscopic methods or consider molecular approaches in the absence of scale separation. Heterogeneous multiscale methods have the capability of bridging the gap between macroscopic and microscopic scales. This study presents the development of a multiscale method in which a diffuse interface method is used to capture the flow around a planar interface while the fluid properties at the interface are evaluated using non-equilibrium molecular dynamic (NEMD) simulations. Different models for dodecane are compared and the interface structure obtained from NEMD simulations is validated against MD results and experimental data.