Investigation the effects of using the renewable alternative fuels in diesel engines on performance and emissions

Diesel engines commonly have been begun to use on especially light duty vehicles in recent years due to reasons of the high efficiency, high torque, increased engine speed, durability and lower carbon monoxide (CO) and hydrocarbon (HC) emissions compared to gasoline engines. However, diesel engines emits a high percentage of nitric oxides (NOx), smoke and particulate matter (PM) when operates with petroleum based fuels. Several methods have been applied in diesel engines to get fuel economy and decrease the harmful exhaust emissions. Among these methods, the addition of various alternative fuels into the conventional fuels to improve their properties and using of some renewable alternative fuels instead of conventional fuels are regarded as a promising solution to reduce the pollutant emissions and meet the future energy demand. Alternative fuels that can be used in diesel engines are listed as natural gas, hydrogen, biogas, biodiesel and various synthetic fuels. Additionally, oxygen containing fuels such as methanol, ethanol, biodiesel and various ethers can be added to diesel fuel at different ratios to improve its properties. In this study, the effects of various renewable alternative fuels which are suitable for diesel engines by using pure or an additive in diesel engines on engine performance and exhaust emissions have been investigated as theoretically and experimentally. Keywords: Diesel engines, Exhaust emissions, Engine performance, Oxygenates, Renewable alternative fuels