Homogeneous nucleation and bubble evolution inside a fuel droplet trigger the occurrence of flash boiling, which shows a high potential to improve the droplet evaporation. To understand the bubble dynamic characteristics, an analytical study on homogeneous nucleation and bubble evolution has been performed, based on the flash boiling model proposed in our work. First, the nucleation rate graph of seven fuels within a wide range of operating temperatures is obtained according to the homogeneous nucleation model. Then the variation of homogeneous nucleation characteristics with fuel temperature and ambient pressure is discussed. Finally, the bubble evolution and boiling explosion of a single droplet are studied for different fuels at 490 K, 530 K, and 560 K, respectively. The results show that the nucleation characteristics are mainly affected by the fuel physical properties, especially the boiling point and surface tension. Moreover, the transitional and heat transfer controlled stages during bubble evolution are significantly affected by the nucleation rate, which causes temperature change and affects the boiling explosion time.

燃料小滴内的均相成核和气泡生成会触发闪蒸的发生，这显示出改善小滴蒸发的巨大潜力。为了理解气泡的动力学特性，基于我们工作中提出的闪蒸模型，对均相形核和气泡演化进行了分析研究。首先，根据均匀成核模型，获得了在宽工作温度范围内的七种燃料的成核率图。然后讨论了均匀成核特性随燃料温度和环境压力的变化。最后，分别针对490 K，530 K和560 K的不同燃料研究了单个液滴的气泡演化和沸腾爆炸。结果表明，成核特性主要受燃料物理性能的影响，尤其是沸点和表面张力。此外，气泡形成过程中过渡和传热控制阶段受成核速率的影响很大，成核速率会引起温度变化并影响沸腾爆炸时间。