Influence of fuel injection pressures on Calophyllum inophyllum methyl ester fuelled direct injection diesel engine

• Effect of injection pressure of Calophyllum inophyllum biodiesel is investigated.
• Engine characteristics of 100% Calophyllum inophyllum biodiesel has been performed.
• Calophyllum inophyllum is a non-edible source for biodiesel production.
• Increase in injection pressure of biodiesel, improves the fuel economy.
• Incylinder pressure characteristics of biodiesel follows similar trend as of diesel.

The trend of using biodiesels in compression ignition engines have been the focus in recent decades due to the promising environmental factors and depletion of fossil fuel reserves. This work presents the effect of Calophyllum inophyllum methyl ester on diesel engine performance, emission and combustion characteristics at different injection pressures. Experimental investigations with varying injection pressures of 200 bar, 220 bar and 240 bar have been carried out to analyse the parameters like brake thermal efficiency, specific fuel consumption, heat release rate and engine emissions of direct injection diesel engine fuelled with 100% biodiesel and compared with neat diesel. The experimental results revealed that brake specific fuel consumption of C. inophyllum methyl ester fuelled engine has been reduced to a great extent with higher injection pressure. Significant reduction in emissions of unburnt hydrocarbons, carbon monoxide and smoke opacity have been observed during fuel injection of biodiesel at 220 bar compared to other fuel injection pressures. However oxides of nitrogen increased with increase in injection pressures of C. inophyllum methyl ester and are always higher than that of neat diesel. In addition the combustion characteristics of biodiesel at all injection pressures followed a similar trend to that of conventional diesel.