Faculty Publications
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Item Effect of bioethanol–diesel blends, exhaust gas recirculation rate and injection timing on performance, emission and combustion characteristics of a common rail diesel engine(Taylor and Francis Ltd. michael.wagreich@univie.ac.at, 2019) Lamani, V.T.; Baliga M, A.U.; Yadav, A.K.; Kumar, G.N.This investigation is focused on the effect of exhaust gas recirculation (EGR) and injection timing on the performance, combustion and exhaust emission characteristics of common rail direct injection (CRDI) engine fueled with bioethanol-blended diesel using computational fluid dynamics (CFD) simulation. Simulation is carried out for various EGR rates (0, 10, 20 and 30%), two different injection timings, and two different bioethanol–diesel blends (10 and 20%) at injection pressure. The equivalence ratio is kept constant in all the cases of bioethanol–diesel blends. The results indicate that the mean CO formation and ignition delay increase, whereas mean NO formation and in-cylinder temperature decrease, with increase in the EGR rate. Further, with an increase in percentage of the bioethanol blends, CO and soot formation decrease as compared to neat diesel. A significant increase in in-cylinder pressure (15%) is found at 14° before top dead centre (BTDC) compared to 9° BTDC, which leads to an increase in indicated thermal efficiency of 4% for neat diesel at 30% EGR. In the present study, maximum indicated thermal efficiency is obtained in the case of 10 and 20% bioethanol–diesel blend, and remains constant for all EGR rates considered in the study. Obtained results are validated with the available literature data and indicate good agreement. © 2017, © 2017 Informa UK Limited, trading as Taylor & Francis Group.Item Impact of 1-Hexanol/diesel blends on combustion, performance and emission characteristics of CRDI CI mini truck engine under the influence of EGR(Elsevier Ltd, 2020) Santhosh, K.; Kumar, G.N.Biofuels are the most promising sustainable and renewable alternative to diesel fuel. In the present renewable energy world, alcohols are gaining prime importance due to their nature of production and fuel properties. The present work aims to investigate the impact of 1-Hexanol and exhaust gas recirculation (10% and 20%) on engine characteristics of the common rail direct injection compression ignition engine. The experiment is carried out on a bench engine. The fraction of 1-Hexanol is varied from 10% to 40% in a step of 10% by volume. The results demonstrate that the use of 1-Hexanol/diesel blends lowers the cylinder pressure and mean gas temperature, which is 4.25% and 1.88% lower at 60% load for 40% 1-Hexanol compared to neat diesel fuel operation. The combustion duration is increased by 2.66?CA for 40% 1-Hexanol at 60% load compared to neat diesel fuel. However, an improvement in net heat release rate is noted which is 13.95% higher at 60% load for 40% 1-Hexanol, this increment is due to prolonged ignition delay. With the use of 1-Hexanol in the engine, there is a drastic reduction in nitrogen oxide emission is observed, this is the greatest impact of 1-Hexanol. However, a slight increment in the hydrocarbon and carbon monoxide emission is also noted due to poor fuel properties like lower cetane number, higher viscosity and higher latent heat of evaporation of 1-Hexanol. Compared to all other blends in the test 10% 1-Hexanol shows comparable results with pure diesel fuel, which is only 2.37% lower in brake thermal efficiency, 3.6% higher in brake specific fuel consumption, 17.55% lower in nitrogen oxide emission, 18.18% higher in hydrocarbon and 33.33% higher in carbon monoxide emission is noted. The exhaust gas recirculation helps in reducing the NOx emission, 40% 1-Hexanol is less sensitive to exhaust gas recirculation. Up to 40% of 1-Hexanol can be used in the CI engine without any modification. It is concluded that 1-Hexanol is a sustainable renewable biofuel due to the reason that even though the use of 1-Hexanol lowers the performance which helps in reducing the NOx emission greatly; the performance can be improved by modifying the engine parameters. © 2020 Elsevier LtdItem Effect of fuel preheating on performance, emission and combustion characteristics of a diesel engine fuelled with Vateria indica methyl ester blends at various loads(Academic Press, 2022) Kodate, S.V.; Raju, P.S.; Yadav, A.K.; Kumar, G.N.The present study examines the preheated (95 °C) and unheated (35 °C) Vateria indica methyl ester (VIME) blends by studying the engine performance, combustion, and emission characteristics at various loads. A single-cylinder, TV1 Kirloskar direct injection diesel engine is used to carry out the tests. Biodiesel produced from Dhupa fat through the transesterification process is used as a renewable fuel in a diesel engine. In this work, diesel (B0), VIME (B100), and two binary blends (B30 and B50) are used. VIME has a higher viscosity, higher density, and lower calorific value than diesel, resulting in lesser brake thermal efficiency (BTE) and higher brake specific energy consumption (BSEC). Due to high viscosity of the biodiesel, preheating of fuel is done before injecting into cylinder. Preheating reduces the viscosity, and enhances the atomization and vaporization of fuel, resulting in improved engine performance. For a given blend of VIME biodiesel and diesel, the preheated blend has better BTE, decreased BSEC and lesser CO and HC emissions, with a slight increment in NOX emission compared to the unheated blend. The preheated B30 blend has a BTE value of 30.3% which is close to the BTE value of 30.1% of unheated diesel at 100% load condition. CO, HC, and soot emissions are decreased by 16.2%, 34.4%, and 16.5%, respectively, for preheated B100 fuel compared to unheated B100, at full load. © 2021 Elsevier Ltd
