Performance and Emissions Characteristics of Alternative Biodiesel Fuel on Small Diesel Engine

Alternative fuels for diesel engines have become increasingly important due to several socioeconomic aspects and increased environmental concerns. Global warming concerns due to the production of greenhouse gases (GHGs) have seen as one of major factor the promotion of the use of biofuels. Carbon dioxide (CO2) from fuel combustion is a major contributor to GHGs and caused a shift in the climate system. Yet the use of biodiesel as an alternative fuel for petroleumdiesel fuel operates in compression ignition (CI) diesel engines is very effective for the reduction of CO2 emission since it is classified as green and renewable energy. It is now acknowledged that the use of the biodiesel blends fuel is restricted due to loss of efficiency and long term problems in the engine associated with worsen the atmosphere pollution. Hence, this study targets on investigating the effects of various biodiesel and fossil diesel blends fuel on engine performance and exhaust gas emissions of small diesel engine and yet recommends bio-fuel that optimise the engine performance and lower exhaust emissions. As results of experimental investigations, there has been a decrease in performance of torque, brake power, brake thermal efficiency (BTE) and brake mean effective pressure (BMEP) while increase in brake specific fuel consumption (BSFC) has been observed for all biodiesel blend fuels over the entire speed range and load test compared to diesel fuel (DSL). In conjunction, exhaust gas emissions, signified the higher formations of NOx emissions while reductions of CO, CO2 and HC gases corresponding to the increasing of biodiesel blending ratio. Increased blends of biodiesel ratio is found to enhance the combustion process consequently decreased the emission elements. It can be concluded that biodiesel blend fuels can be used in diesel engines without any engine modifications and have beneficial effects both in terms of emission reductions and alternative petroleum diesel fuel.