Performance enhancement and emissions mitigation of DI-CI engine fuelled with ternary blends of jatropha biodiesel-diesel-heptanol

Abstract

The rising consumption of fossil fuels has lead to massive depletion of the petroleum reserves. The combustion of diesel has contributed to serious environmental problems which prove to be detrimental for human life and biodiversity. In order to meet the challenges of energy security and pollution control, researchers have come with ternary blends comprising of jatropha biodiesel-diesel-alcohol blend in different volumetric proportions. Ternary blends can serve the dual purpose of alternate and sustainable fuel for the modern transport sector. Besides, they offer huge potential in improving the engine performance and lowering the exhaust emissions. Biodiesel and alcohol are derived from renewable sources of agricultural feed stocks. The physical–chemical properties of both biodiesel and alcohol are similar to those of conventional diesel. Many studies have reflected that higher alcohols prove to be better additives than lower alcohols in biodiesel. The present work deals with the analysis of performance and emissions of diesel engine fueled with ternary blends. The preparation of four test fuel samples (ternary blends) were done, namely DBHep10 (D = 40%, B = 50%, Heptanol = 10%), DBHep20 (D = 40%, B = 40%, Heptanol = 20%), DBHep30 (D = 40%, B = 30%, Heptanol = 30%) and DBHep40 (D = 40%, B = 20%, Heptanol = 40%). The test fuels were tested in CRDI diesel engine at varied engine loads of 5 Nm, 10 Nm, 15 Nm and 20 Nm, while the engine speed was kept constant at 1800 rpm. The ternary blends resulted in higher BTE and lower BSFC with increased volumetric proportion of heptanol. The CO and UHC emissions were reduced for ternary blends than diesel, however NOx emission got increased. The use of heptanol up to 40% as additives in biodiesel-diesel blends showed huge potential as alternate and sustainable fuel.