Faculty Publications
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Item Analysis of Cyclic Variations and Combustion Behavior of Liquid Phase Hydrocarbons Under Uniform Axial and Radial Magnetic Fields(Springer Science and Business Media Deutschland GmbH, 2023) Oommen, L.P.; Kumar, G.N.The present study experimentally investigates the combustion characteristics of a multi-cylinder MPFI spark ignition engine fuelled by gasoline under uniform magnetic fields. Permanent magnets made of N38 grade NdFeB are used to magnetize the liquid phase hydrocarbons and the impact produced on combustion characteristics like in-cylinder pressure and net heat release rate are studied under different speeds and load conditions of the engine operation. Three different magnetic intensities (3200 G, 4800 G, and 6400 G) are employed in two different magnetization patterns (axial and radial) at an inbuilt ignition timing of 5 deg bTDC. Magnetic field assisted combustion is observed to enhance the performance characteristics of the engine, while simultaneously reducing the exhaust emissions to a significant level. A statistical analysis of cyclic fluctuations in magnetic field-assisted combustion is also made which shows a reduction in fluctuations (COV) with the application of each stage of ionization. The increase observed in peak pressures and heat release rates along throughout the combustion cycles with reduction in cyclic variations indicate that magnetic field-assisted combustion exhibits better combustion characteristics as compared to normal gasoline combustion. © 2023, The Author(s), under exclusive license to Springer Nature Singapore Pte Ltd.Item Combustion Characteristics and Cyclic Variation of a LPG Fuelled MPFI Four Cylinder Gasoline Engine(Elsevier Ltd, 2016) Nayak, V.; Rashmi, G.S.; Chitragar, P.R.; Mohanan, P.Present study deals with to investigate the effect of dual mode of operation on combustion characteristics of engine and cyclic variation in a modified multi-cylinder SI engine. Experiments will be conducted with baseline gasoline and later with dual fuel mode of experiments i.e., gasoline with LPG with different ratios (25%, 50%, 75% and 100% of LPG by mass). Experiment will be carried out with varying speed from 2000 rpm to 4500 rpm in steps of 500 rpm at full load condition with factory set static ignition timing of 5 deg. bTDC to investigate combustion characteristics and cyclic variations. Results revealed that as the LPG percentage increases the peak pressure also increases and it is maximum for 100% LPG for all the speed. At 4500 rpm the percentage increase in peak pressure is 20% for 100% LPG, 9% for 25%LPG, 3% for 50%LPG, 1% for 75%LPG when compared to gasoline at full load. This increase in peak pressure will indicate the LPG will give better combustion properties compared to that of gasoline. Compared to peak pressure, the variation in cycle to cycle for IMEP is less.Net heart release rate shows that gasoline will give the more heat release compare to all other fuels, but LPG will release the heat little earlier than gasoline. Since peak pressure is near to TDC for LPG which results in NHRR to occur earlier than gasoline. Final outcome of the research is LPG will have better combustion properties compared to gasoline but cyclic fluctuations are more for LPG. © 2016 The Authors.Item An Experimental Study on Combustion and Emission Analysis of Four Cylinder 4-Stroke Gasoline Engine Using Pure Hydrogen and LPG at Idle Condition(Elsevier Ltd, 2016) Chitragar, P.R.; Shivaprasad, K.V.; Nayak, V.; Bedar, P.; Kumar, G.N.Fluctuation in oil prices and stricter exhaust emission norms were the main reasons wakening every researcher to search for suitable and feasible alternative fuels for automotive use. Among the available option gaseous fuels find their best position because of their compatible physical-chemical properties and ecofriendly nature than present fossil fuels. Hydrogen's combustion properties like high energy content, high heating value, wide range of flammability and low ignition energy with almost least toxic emissions are favorable to use in an IC engine as an alternative fuel. Liquid petroleum gas (LPG) has lower carbon content, higher calorific value, octane number and flame propagation speed will improve the emission results compared to gasoline fuel. This paper describes an experimental results carried out to evaluate the combustion and emission performance of a Maruti Suzuki make, spark ignited four cylinders, four stroke engines at idle condition by using pure hydrogen, LPG and gasoline. The engine was adjoined with Electronic Control Unit (ECU) assisting hydrogen and LPG injector system keeping gasoline line unchanged. Tests were carried out by using compressed hydrogen gas regulated by two stage pressure reduction from cylinder to atmospheric value and by using vaporizer pressure for LPG. For comparison engine was run first by gasoline and then by pure hydrogen and LPG. Study revealed that there was increment of 13% cylinder pressure for pure hydrogen and decrement of 4.5% cylinder pressure for LPG when compared to gasoline. The burn duration for pure hydrogen, LPG and gasoline were found to be increasing respectively which infers that hydrogen has very short combustion duration and gasoline higher. It was observed that toxic emissions like Carbon monoxide (CO), Hydrocarbons (HC) and Oxides of Nitrogen (NOx) were improved for pure hydrogen than LPG and gasoline. © 2016 The Authors.Item Performance Emission and Combustion Characteristics of CRDI Engine Operating on Jatropha Curcas Blend with EGR(Elsevier Ltd, 2018) Bedar, P.; Kumar, G.N.The present experimental study uses dual cylinder common rail direct injection (CRDI) engine fuelled by Jatropha curcas biodiesel blends produced through Transesterification process along with application of water cooled exhaust gas recirculation (EGR) rates. Performance, emissions and combustion properties of an engine at constant speed were measured and analysed. The improvement in brake thermal efficiency (BTE) along with reduction in carbon monoxide (CO), unburned hydrocarbons (UBHC) and smoke opacity were observed for the B20 biodiesel blend with a marginal increase in oxides of nitrogen (NOx). EGR application has reduced the NOx emissions and peak pressure inside the combustion chamber due to lower flame temperature. Combining B20 blend ratio with 15% EGR rate has the potential to achieve ultra-low NOx without affecting other type of diesel engine exhaust emissions by maintaining same efficiency level. © 2018 Elsevier Ltd.Item Experimental Studies on the Effect of Varying Rates of Part-Cooled EGR in High Pressure Loop on an MPFI Engine Under Variable Speed Operation(Springer Science and Business Media Deutschland GmbH info@springer-sbm.com, 2021) Oommen, L.P.; Kumar, G.N.Researches in automobile sector around the globe are focused on meeting the currently proposed emission norms. Exhaust gas recirculation is one pre-treatment technique that has been found effective in enhancing the combustion and emission characteristics of IC engines and regulating the emission of nitrogen oxides. The present work analyses the effect produced by different rates of partially cooled EGR in a high pressure loop on a multi-cylinder MPFI gasoline engine. Three flow rates of EGR—12%, 18% and 24%—have been studied, and the impact produced on thermal efficiency, specific fuel consumption and emission of macropollutants of the test engine has been analysed under variable speed operation in comparison with normal operation of the engine without recirculation. The temperature of recirculated exhaust gas is so maintained as not to have a negative influence on the fuel consumption characteristics. A reduction in specific fuel consumption is observed which results in a marginal improvement of brake thermal efficiency alongside the advantage obtained in the emissions of the engine. The study proves that the advantages of EGR addition are limited to around 18% above to which the cyclic variations and misfires become predominant, deteriorating the performance and emissions of the test engine. © 2021, Springer Nature Singapore Pte Ltd.Item Combustion and emission characteristics of a dual fuel engine operated with mahua oil and liquefied petroleum gas(Serbian Society of Heat Transfer Engineers, 2008) Nadar, K.N.; Reddy, R.P.For the present work, a single cylinder diesel engine was modified to work in dual fuel mode. To study the feasibility of using methyl ester of mahua oil as pilot fuel, it was used as pilot fuel and liquefied petroleum gas was used as primary fuel. In dual fuel mode, pilot fuel quantity and injector opening pressure are the few variables, which affect the performance and emission of dual fuel engine. Hence, in the present work pilot fuel quantity and injector opening pressure were varied. From the test results, it was observed that the pilot fuel quantity of 5 mg per cycle and injector opening pressure of 200 bar results in higher brake thermal efficiency. Also the exhaust emissions such as smoke, unburnt hydrocarbon and carbon monoxide are lower than other pressures and pilot fuel quantities. The higher injection pressure and proper pilot fuel quantity might have resulted in better atomization, penetration of methyl ester of mahua oil and better combustion of fuel.Item Performance and emission characteristics of a Kirloskar HA394 diesel engine operated on fish oil methyl esters(2010) Godiganur, S.; Suryanarayana Murthy, Ch.; Reddy, R.P.The high viscosity of fish oil leads to problem in pumping and spray characteristics. The inefficient mixing of fish oil with air leads to incomplete combustion. The best way to use fish oil as fuel in compression ignition (CI) engines is to convert it into biodiesel. It can be used in CI engines with very little or no engine modifications. This is because it has properties similar to mineral diesel. Combustion tests for methyl ester of fish oil and its blends with diesel fuel were performed in a kirloskar H394 DI diesel engine, to evaluate fish biodiesel as an alternative fuel for diesel engine, at constant speed of 1500 rpm under variable load conditions. The tests showed no major deviations in diesel engine's combustion as well as no significant changes in the engine performance and reduction of main noxious emissions with the exception on NOx. Overall fish biodiesel showed good combustion properties and environmental benefits. © 2009 Elsevier Ltd. All rights reserved.Item An analysis of cycle-by-cycle fluctuation in combustion parameter in CI engine operation for various bio-fuels(2011) Bekal, S.; Ashok Babu, T.P.A.The cycle-by-cycle fluctuations in peak pressure of combustion in a CI engine were studied for lower and higher blends of diesel and ester, and water-in-ester emulsions, at four injection timings and three injection pressures using coefficient of variation. The sunflower ester-diesel blends are found to have lower cycle-by-cycle fluctuations than pongemia ester-diesel blends. The fluctuations are found to be higher than that of diesel for higher blend proportions of ester. The water-in-ester emulsion show higher cycle-by-cycle fluctuations than that of ester-diesel blends. In most cases, the Brake specific energy consumption is also found to be higher where the coefficient of variation has higher values. Copyright © Taylor & Francis Group, LLC.Item Effect of oxygen enrichment on the performance, combustion, and emission of single cylinder stationary CI engine fueled with cardanol diesel blends(Korean Society of Mechanical Engineers, 2014) Dinesha, P.; Nayak, V.; Mohanan, P.We investigated the effect of intake air enrichment on the performance, combustion, and emission characteristics of a single cylinder direct-injection stationary diesel engine fueled with non- edible alternative fuel, namely, cardanol - diesel - methanol blend (B20M10). The results were compared with baseline diesel operations under standard operating conditions. The bio-fuel blend B20M10 (20% cardanol, 10% Methanol, and 70% diesel) was used as fuel and the combustion, performance, and emission characteristics were investigated by oxygen enriching of intake air with 3, 5, and 7 percentage by weight. With the increase of intake air oxygen concentration, CO, HC, and smoke were found to be decreased. But BTE and NOx emission were considerably increased. The blended fuel B20M10 with 7% oxygen enrichment of intake air was compared with diesel operation. The results show a 0.5% lesser BTE, 28% more NOx emission at full load condition. There is not much variation of smoke emission to be noticed for this fuel combination compared to diesel. © 2014 The Korean Society of Mechanical Engineers and Springer-Verlag Berlin Heidelberg.Item A study of the effect of injection pressure on the combustion, performance, and emission characteristics of cardanol biofuel blend fuelled compression ignition engine(John Wiley and Sons Ltd Southern Gate Chichester, West Sussex PO19 8SQ, 2015) Dinesha, P.; Mohanan, P.The use of biodiesel along with other alternative fuel sources is expected to address the twin problems of pollution and energy security. This study investigates the effect of injection pressure (IP) on the performance, combustion, and emission characteristics of a four-stroke single cylinder direct injection diesel engine fuelled with a biofuel, namely cardanol-methanol-diesel blend (B20M10). The results are compared with baseline diesel operations under standard operating conditions. The biofuel blend B20M10 (20% cardanol, 10% methanol, and 70% diesel) is used as fuel, and the combustion, performance, and emission characteristics are investigated at IP levels of 180, 200, and 220 bar. The test results show that the optimum fuel IP is 220 bar with B20M10. At this optimized pressure, a reduction in CO, HC, and smoke emissions with an increase in the oxides of nitrogen (NOx) and brake thermal efficiency (BTE) are noticed compared with 180 and 200 bar B20M10 operations. When compared with diesel (180 bar IP), B20M10 blend at 220 bar IP gives marginally lower BTE and lower CO and HC emissions, but oxides of nitrogen and smoke are slightly more. © 2014 Curtin University of Technology and John Wiley & Sons, Ltd.