Ignition Delay of Oxygenated Fuel Droplets

摘要

Biodiesel has been shown to be effective in reducing CO, HC, and PM emissions from diesel engines; decreasing dependence on petroleum imports; and developing new markets for agricultural products such as soybeans. However, most studies have also shown that NO_x emissions increase with biodiesel versus petroleum based diesel The reason for the increased NO_x emissions from biodiesel has yet to be fully explained, although recent studies have attributed it to differences in physical properties between biodiesel and petroleum diesel. The first mechanism is related to the higher boiling point range of biodiesel with respect to petroleum diesel. The higher boiling point range enables fuel droplets to penetrate further into the cylinder, thereby increasing the amount of fuel consumed during the premixed ignition process. The increased fuel consumption is accompanied by increased heat release, which results in higher NO_x emissions.