Novel Methodology to Utilise Neem (Azadirachta Indica) Oil in a Direct Injection Compression Ignition Engine: Performance and Emissions Characterization 2009-28-0039

The world energy demand has witnessed uncertainties in two dimensions. The scarcity and depletion of conventional petroleum sources are causes of great concern worldwide. Combustion of fossil fuels has led to unprecedented rise in the global CO₂ level, leading to global warming. Therefore, efforts are underway in several countries to search for suitable alternative fuels that are environment friendly. Vegetable oils of non-edible nature are such alternative fuels, which can form part of potential solution. Vegetable oils, due to their agricultural origin, are able to reduce CO₂ emissions to the atmosphere along with import substitution of petroleum products

In the present research, experiment were designed to study the effect of reducing Neem oil's high viscosity by increasing the fuel temperature and thereby its effect on combustion and emission characteristics of the engine. Experiments were also conducted using various blends of Neem oil with mineral diesel to study the effect of reduced blend viscosity on emissions and performance of diesel engine. A single cylinder, four stroke, constant speed, water cooled, direct injection diesel engine typically used in agricultural sector was used for these experiments. The experimental data was analyzed for various performance and emission parameters such as brake thermal efficiency, brake specific fuel consumption (BSFC), smoke opacity and emissions of CO₂, CO, and HC. While operating the engine on Neem oil (preheated and blends), performance and emissions parameters were found to be very close to mineral diesel for lower blend concentrations. However, for higher blend concentrations, performance and emissions were observed to be slightly inferior to that of mineral diesel.