The influence of air swirl and exhaust gas recirculation on combustion and emissions in a diesel engine using biodiesel blends

Abstract

The petroleum crisis in the recent years has stimulated a world-wide search for newlinealternative fuels. Bio-Diesel is an attractive alternative fuel which is renewable, nontoxic, newlineless carbon monoxide and hydrocarbon emissions due to higher content of oxygen. newlineThe Bio-Diesel has high cetane number which is a measure of fuel s ignition quality. It newlinereplaces the exhaust odour of petroleum diesel with more pleasant smell. newlineThe objective of this study is to investigate the usage of Bio-Diesel blends, effect newlineof swirl inducement for better fuel air mixing and exhaust gas re-circulation in order to newlinereduce NOx emission along with other regulated pollutants from a diesel engine. For the newlineexperimental work, a single cylinder, naturally aspirated water cooled direct injection newlinediesel engine is used for experimental work and observed the engine performance newlineparameters such as brake thermal efficiency, brake specific fuel consumption, exhaust newlinegas temperature and emission characteristics. newlineThe present work is aimed at studying the effects of modifications in fuel and newlinefuel-air mixing process respectively for improving diesel engine combustion and newlineemission characteristics. The total investigation is divided into three stages; newlineFirst stage: Use of the Bio-Diesel as an alternative fuel newlineSecond stage: In-cylinder turbulence inducement through the grooves on the piston newlinecrown. newlineThird stage: Exhaust gas recirculation. newlineStage I (Usage of Karanja Bio-Diesel blends): Karanja oil (Pongamia Pinnata) is newlinenon-edible in nature and is available abundantly in India. An experimental investigation newlineis made to evaluate the performance, emission and combustion characteristics of a diesel newlineviii newlineengine using different blends of Karanja Bio-Diesel with diesel. Karanja oil is blended newlinewith diesel in proportions of 15% ( K15), 20% (K20) and 25% (K25), by volume and newlinestudied under various load conditions in a diesel engine. The performance parameters newlinewere found to be very close to that of diesel. Further it is observed that the performance is newlinebetter than diesel for K20 blend