Abstract
Biodiesel – one of the best candidates for diesel fuels in compression ignition engines – is biodegradable and nontoxic; has low emission profiles; and is also environmentally beneficial. The fuel is briefly defined as methyl or ethyl esters generated organic compounds and derived from a broad variety of renewable resources such as vegetable oils, and animal fats. The fuel can be produced by four basic methodologies including direct use of vegetable oils, microemulsion, pyrolysis, and transesterification. In this paper, one-cylinder engine model is built based on GTPower simulation. The engine is operated on renewable fuel - biodiesel and diesel mixtures in a range of engine speed between 1,000 and 2,000 rpm and the blend compositions of 5%, 10%, 20%, 50% and 100%. The simulation results show 3-5% reduction in engine power, 50% increase in NOx, but up to 45% decrease in SOOT when the engine operates on the biodiesel and diesel mixtures. The results may help the authors to have future tests in a Cooperative Fuel Research (CFR) engine or in an optical access engine to clarify the physical and chemical properties of biodiesel as well as the engine performance when operated on this fuel. The high NOx level may due to a difference between ignition delay of biodiesel and diesel and may suggest for the application of variable injection timing, NOx reduction technology such as EGR, common-rail, turbocharger, or after treatment technology in the CI engines in order to help the engine comply with current emission standards.
Keywords: Biodiesel, Emissions, Fuel consumption, CI engine, GT-power simulation