Influence of combustion chamber geometry on the combustion and emission characteristics of a direct injection diesel engine operated on renewable and sustainable fuel derived from diary scum waste

Abstract

Present work discusses experimental investigation to study the effect of biodiesel blends and re-entrant combustion chamber on the performance, combustion and exhaust emissions. In the first phase of the work, diary scum oil methyl ester (DiSOME) biodiesel was produced by conventional transesterification process and is blended with conventional diesel fuel in steps of 20 (by volume). Further in the next phase of the work, influence of blended fuel properties and re-entrant combustion chamber (RCC) on the combustion and emission characteristics of a direct injection diesel engine has been investigated. Results of investigation showed that B20 operation with RCC provided increased thermal efficiency by 3-4% with 10% increased smoke, 10-20% decreased hydrocarbon (HC) and carbon monoxide (CO) and 8-10% increased nitric oxide (NOx) emission levels compared to B100 operation. Further increased cylinder pressure and heat release rate were observed with B20. However, Thermal efficiency and NOx emissions are comparatively lower and smoke, HC and CO emissions were found to be slightly higher than base line diesel operation.