Combustion and emission characteristics of a compression ignition engine operated on dual fuel mode using renewable and sustainable fuel combinations

Abstract

The present experimental study aims to examine the combustion and emission characteristics of a single cylinder four stroke direct injection diesel engine operated in dual fuel mode using dairy scum oil methyl ester (DiSOME) and its blend (B20)—producer gas combination with and without addition of hydrogen. DiSOME/B20-producer gas combination without hydrogen addition exhibited inferior performance with increased hydrocarbon and carbon monoxide emissions owing to poor physic-chemical properties of both biodiesel and inducted low calorific value gas (producer gas) compared to the same fuel combination with hydrogen. Producer gas was inducted along with air, and hydrogen was allowed to mix with air-producer gas combination in the intake manifold. Experimental investigations were conducted at all load conditions and at constant flow rate of hydrogen (8 lpm). It was noticed that that B20-hydrogen enriched producer gas combination with optimum parameters resulted in amplified thermal efficiency with reduced emission levels compared to the operation with B20/DiSOME-producer gas combination. However, investigation showed that diesel-producer gas combination with hydrogen addition provided amplified brake thermal efficiency by 3.8%, 16.4% and 13.2% compared to the diesel/DiSOME/B20—producer gas combinations, respectively, at 80% load. Hydrogen addition provided enhanced cylinder pressure and heat release rate with reduced emission levels except nitric oxide emissions. It can be concluded that the deprived combustion associated with DiSOME/B20-producer gas combination can be improved with hydrogen addition. The combination of DiSOME-producer gas operation with hydrogen addition is uniqueness of this present work.