Modeling and Simulation of Nano-Fuel Droplet Evaporation With the Lattice Boltzmann Approach

Abstract The multiple-relaxation-time (MRT) pseudopotential model coupled with the color-gradient multiphase approach was employed to numerically investigate the evaporation dynamics of a single CeO2 nano-fuel droplet. The study focused on elucidating the effects of nanoparticle concentration and particle diameter on the evolution of concentration and temperature fields during the evaporation process. Simulation results indicate that the internal concentration of the nano-fuel gradually increases as evaporation proceeds. A higher nanoparticle concentration and a smaller particle diameter accelerate the overall evaporation rate by enhancing internal heat transfer and interfacial energy exchange. The droplet temperature continuously rises as it absorbs heat from the surrounding environment, leading to the formation of a temperature gradient between the droplet and the ambient gas. This heat transfer induces the development of an outwardly expanding thermal boundary layer along the droplet surface, which promotes the liquid–vapor phase transition and shortens the time required to achieve thermal equilibrium.