Autoignition of Biodiesel, Methanol, and a 50:50 Blend in a Simulated Diesel Engine Environment

Autoignition delay times of diesel, methanol, biodiesel, and 50 wt%, 25 wt%, and 10 wt% biodiesel in methanol were measured in a constant-volume combustor. The autoignition delay times of biodiesel are similar to diesel and confirm the utility of biodiesel as a direct diesel alternative. While methanol has poor ignition characteristics, the 50 wt% blend performed similar to diesel. The 25 wt% and 10 wt% blends had ignition delay times between those of methanol and biodiesel. Methanol and biodiesel have a synergy in blends where the favorable ignition delay times of biodiesel and lower viscosity and cost of methanol combine to provide a better fuel.