Different blend ratio of ternary component fuel was tested inside a constant volume chamber to investigate fuel injection and combustion under similar real engine working conditions. Because liquid spray light scattering is the different reflective rate from the liquid droplets and its surrounding background, butanol-biodiesel-diesel liquid jet penetration length can be highlighted in the images taken by high speed camera. Various ambient temperatures from 800K to 1200K and fuel composition were investigated. Measured results showed that sudden but repeatable drop of liquid jet penetration length at constant ambient temperature conditions of 800K and 900K. With ambient temperature increasing, this phenomenon became weak and disappeared. So more works focus on non-combusting experiments in order to delete combustion reflect. With butanol and biodiesel content increasing, micro explosion becomes prone excited and more violent because of the enlarged differences in volatilities and boiling point among the components. It is concluded that micro explosion which will distinctly enhances premixed combustion process and heat release rate but it present under certain initial ambient temperature conditions only and the light fuel content shouldn’t be lower than 10%.
Liquid jet penetration and breakup in a free supersonic gas jet