Numerical Study on the Effect of Pressure on Biodiesel/N-Pentanol Blended Droplet Homogeneous Micro-Explosion

Department of Thermal Science and Energy Engineering, University of Science and Technology of China, Hefei 230026, China

^* Corresponding author: mhliu@ustc.edu.cn
^a xhk@mail.ustc.edu.cn

Abstract

A three-dimensional droplet evaporation model using VOF is developed to study the influence of pressure on biodiesel/n-pentanol blended droplet homogeneous nucleation and evaporation characteristics. Numnerical results reveal that the homogeneous nucleation ratereduces while the homogeneous superheating limit temperature increases with increase of the pressure and the critical n-pentanol mole fraction. The minimum n-pentanol mole fraction of 0.65 is required for homogeneous nucleation when the ambient pressure is 12 atm. Higher pressure also weakens surface evaporation of droplets, which reduces the increase rate of vapor concentration around droplets, and increases the peak vapor value. The homogeneous micro-explosion can only occur when the ambient pressure is greater than 3 atm. As pressure increases, the temperature and temperature rise rate of droplets increases, and the homogeneous micro-explosion delay reduces.