Fellow 2000-01

Chia-Fon Lee

Mechanical Science and Engineering

Assistant professor of mechanical and industrial engineering

Professor Lee joined the UIUC faculty in the fall of 1995. His research includes modeling and numerical techniques for two-phase turbulent reacting flows, internal combustion engines, liquid atomization and vaporization, and spray/wall impingement, and experimental techniques for two-phase flow.

During his Center appointment, he will develop multi-dimensional models for micro-explosion and flash boiling of automotive fuel sprays. Micro-explosion and flash boiling are special phenomena associated with liquid fuel droplet vaporization and atomization. For multicomponent fuel droplets vaporization, light components are entrapped inside the droplet at the middle or later stage of the vaporization process. This may lead to a local super-heat region within the droplet, which produces bubbles inside the droplet when there are nuclation sources. These bubbles undergo a violent expansion resulting in secondary breakup of the droplet (so called micro-explosion). Flash boiling, which occurs at the injector nozzle exit, is physically similar to micro-explosion. Both of them feature a rapid expansion process and have a gas core, and they can have positive effects on combustion performance since they tend to produce smaller droplets compared to conventional breakup mechanisms. Therefore, they have the potential to improve fuel/air mixture preparation. His project will focus on creating a comprehensive model involving the nucleate theory, stability theory and conservation equations. To verify the model, well-controlled laser diagnostic experiments are to investigate the role of micro-explosions and flash boiling on droplet and spray characteristics and to provide the necessary information for modeling.