Ignition delay, combustion and emission characteristics of Diesel engine fueled with rapeseed biodiesel - A literature review

Biodiesel is one of the biodegradable and renewable fuels, which is originated from vegetable oil or animal fats. Rapeseed biodiesel is a kind of biofuel which is gaining acceptance in the market due to many environmental and economic benefits. It can be used alone or in a blend with Diesel fuel, directly in compression ignition engines, without any modifications. This review collects and analyzes published papers concerning the usage of rapeseed biodiesel as an alternative fuel in Diesel engines. It covers engine combustion, performance and emissions characteristics. Research results reveal that rapeseed biodiesel, either pure or blended with Diesel, has lower heat release rate, reduced ignition delay, lower thermal efficiency and higher brake specific fuel consumption. Carbon monoxide (CO) and particulate matter (PM) exhaust emissions are up to 60% lower, while carbon dioxide (CO2) and nitrogen oxides (NOx) are higher in comparison to Diesel fuel. This behavior is explained by the shorter ignition delay and advanced fuel injection when using rapeseed oil.