Simulation study on the single droplet evaporation of N-tetradecane with CeO2 nanoparticles

Abstract

To investigate the influence of CeO2 nanoparticles on the evaporation characteristics of fuel droplets, numerical simulation for single nano-fuel droplet evaporation was conducted based on ANSYS FLUENT software according to the single droplet evaporation visualization experiment. And the effects of nanoparticles’ concentration and size on the temperature and fuel-vapor concentration during the evaporation of were emphatically discussed. The simulation results showed that the temperature field and concentration field were distributed in a gradient. Nano-fuel droplets absorbed heat from the external environment, and the temperature of the nano-fuel droplets kept rising until reaching the evaporation equilibrium temperature. The evaporation equilibrium temperature of nano-fuels droplets was higher than that of N-tetradecane (C14) at the temperature of 573 K. In addition, it increased with the increment of nanoparticle concentration and reduction of the nanoparticle size. In the beginning of the evaporation, the vapor volume fraction of nano-fuel was relatively low and it increased slowly with time. As the evaporation process continued, the evaporation rate of nano-fuel droplets increased. The liquid nano-fuel was constantly evaporating to the fuel vapor, and the vapor volume fraction was increased. The vapor volume fraction was increased during the same evaporation period when elevated nanoparticles concentration and minished nanoparticles size.