Publication

Abstract : Fossil fuel reserves are depleting at an alarming rate and may become extinct in few decades. To counteract this crisis much emphasis is laid out on usage of alternate fuels. Also techniques like turbocharging are used to increase the efficiency of the IC engines thereby reducing the fuel consumption. While opting for such alternate solutions like biodiesel and turbocharging, the exhaust emissions should be checked to ensure that these solutions don't pose a threat to the environment. So in this project the change in amount of component gases in the exhaust emissions were found out in four cases which are naturally aspirated with diesel, turbocharged with diesel, naturally aspirated with biodiesel and turbocharged with biodiesel. A single cylinder motorcycle diesel engine is used in this project. Emission characteristic tests were done in the naturally aspirated engine using diesel and biodiesel as fuels. Then a turbocharger designed for this engine is fitted to it and the same tests as above were conducted. Comparison in exhaust emissions which are NOx, HC, CO and CO2 was made for the above mentioned four cases. It was found that NOx emissions has increased by the usage of biodiesel as fuel, while turbocharger has decreased the NOx levels. This is a concern to be addressed while using biodiesel as alternate fuel. Biodiesel and turbocharger both had a positive effect on HC emissions, i.e. reduced the HC emissions. The impact of biodiesel and turbocharger on CO emissions was not so significant with the former increasing the emissions and the latter decreasing it by providing more oxygen. Though CO2 is not categorised as toxic emissions like other emissions; it is important to compare the amount emitted in the different cases. Biodiesel increases the amount of less-toxic CO2 whereas turbocharger has reduced the CO2 emissions. This is because the excess oxygen provided by turbocharging is used for the formation of water vapour rather than CO2. Thus the important four emissions were compared to appreciate the effect of biodiesel and turbocharger. In future work the problem of increase in NOx by biodiesel fuel should be addressed and solution has to be formulated.