Faculty Publications
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Item Studies on influence of injection timing and diesel replacement on LPG-diesel dual-fuel engine(2003) Sudhir, C.V.; Desai, V.; Suresh Kumar, Y.; Mohanan, P.Reducing the emissions and fuel consumption for IC engines are no longer the future goals; instead they are the demands of today. People are concerned about rising fuel costs and effects of emissions on the environment. The major contributor for the increased levels of pollutants is the Diesel engines. Diesel engine finds application in almost in all fields, including transportation sector such as buses, trucks, railway engines, etc. and in industries as power generating units. In the present work an attempt is made for effective utilization of diesel engine aiming for reduction in fuel consumption and smoke density. This is achieved by some minor modifications in diesel engine, so as to run the existing diesel engine as a LPG-Diesel dual-fuel engine with LPG (Liquefied Petroleum Gas) induction at air intake. The important aspect of LPG-Diesel dual-fuel engine is that it shows significant reduction in smoke density and improved brake thermal efficiency with reduced energy consumption. An existing 4-S, single cylinder, naturally aspirated, water-cooled, direct injection, CI engine test rig was used for the experimental purpose. With proper instrumentation the tests were conducted under various LPG flow rates, loads, and injection timings. The influence of the diesel replacement by LPG on smoke density, brake specific energy consumption and brake thermal efficiency were studied. The optimal diesel replacement pertaining to the maximum allowable LPG gas flow limits could be assessed with these experiments. The influence of the injection timing variation on the engine performance and smoke density were analyzed form the experimental results. It was also observed that beyond half load operation of the dual-fuel engine, the brake thermal efficiency increases with diesel replacement, and at full load up to 4% improvement was observed compared to full diesel operation. At full load reduction in smoke density up to 25-36% was observed compared to full diesel operation. At advance injection timing of 30°btdc the performance was better with lower emissions compared to normal and retarded injection timings. Copyright © 2003 by ASME.Item Studies on influence of injection timing and Diesel replacement on LPG-Diesel dual-fuel engine(2003) Sudhir, C.V.; Desai, V.; Suresh Kumar, Y.; Mohanan, P.Reducing the emissions and fuel consumption for IC engines are no longer the future goals; instead they are the demands of today. People are concerned about rising fuel costs and effects of emissions on the environment. The major contributor for the increased levels of pollutants is the Diesel engines. Diesel engine finds application in almost in all fields, including transportation sector such as buses, trucks, railway engines, etc. and in industries as power generating units. In the present work an attempt is made for effective utilization of diesel engine aiming for reduction in fuel consumption and smoke density. This is achieved by some minor modifications in diesel engine, so as to run the existing diesel engine as a LPG-Diesel dual-fuel engine with LPG (Liquefied Petroleum Gas) induction at air intake. The important aspect of LPG-Diesel dual-fuel engine is that it shows significant reduction in smoke density and improved brake thermal efficiency with reduced energy consumption. An existing 4-S, single cylinder, naturally aspirated, water-cooled, direct injection, CI engine test rig was used for the experimental purpose. With proper instrumentation the tests were conducted under various LPG flow rates, loads, and injection timings. The influence of the diesel replacement by LPG on smoke density, brake specific energy consumption and brake thermal efficiency were studied. The optimal diesel replacement pertaining to the maximum allowable LPG gas flow limits could be assessed with these experiments. The influence of the injection timing variation on the engine performance and smoke density were analyzed form the experimental results. It was also observed that beyond half load operation of the dual-fuel engine, the brake thermal efficiency increases with diesel replacement, and at full load up to 4% improvement was observed compared to full diesel operation. At full load reduction in smoke density up to 25-36% was observed compared to full diesel operation. At advance injection timing of 30°btdc the performance was better with lower emissions compared to normal and retarded injection timings.Item Bio-fuel variants for use in CI engine at design and off-design regimes: An experimental analysis(2008) Bekal, S.; Ashok Babu, T.P.A.In this work an attempt has been made to study the ester based fuel variants derived from edible and inedible oil sources for identifying the most appropriate fuel variant and operating mode for running a CI engine based on performance and emission parameters. The twenty four fuel variants tested included esters obtained from the edible sunflower oil, inedible pongamia oil, and their higher and lower proportional blends with diesel. Besides, several other fuel variants obtained from the emulsification of water-in-ester (W/E) with different water proportions have been tested. Basing upon three operational variables, namely, injection timing, injection pressure, and load, comparisons are made in aspects of smoke emissions, NOX emissions, BSEC, and exhaust gas temperatures at the best injection timing. 21.5°, 23°, 24.5° and 27.5° bTDC as the four injection timings and 190, 220 and 250 bar as three injection pressures are considered for the overall study. The 264 sets of experiments conducted with these combinations, focussing on the full and partial load characteristics of the engine, show that both sunflower and pongamia oil esters exhibited similar characteristics in their engine performance, and in both the cases the best BSEC occurred with 220 bar injection pressure for most of the fuel variants, and for straight fuels the ideal injection timing found to be slightly retarded (1.5° crank angle) compared to diesel. However, 24.5° bTDC, normal for the engine, was found to be the most appropriate for the lower blends like B2 (2% ester by volume), B5 and emulsion with 10% water proportion. © 2008 Elsevier Ltd. All rights reserved.Item Combustion and emission characteristics of di compression ignition engine operated on jatropha oil methyl ester with different injection parameters(2009) Dhananjaya, D.A.; Sudhir, C.V.; Mohanan, P.The current paper reports the engine performance, combustion and emissions from a direct injection compression ignition engine operated with different injector opening pressure (IOP) and injection timing (IT) with jatropha oil methyl ester (JOME) (B100), B20 (20% biodiesel and 80% petroleum diesel fuel which are generally called of B20 fuel) and diesel as test fuels. The engine was run on three different IOP viz. 180, 220 and 240bar along with normal IOP 200bar and two IT viz. 20deg. bTDC and 26deg. bTDC along with normal IT 23deg. bTDC. For all IOP and IT tried, the performance parameters such as brake thermal efficiency (BTE), brake specific energy consumption (BSEC), combustion parameters such as peak cylinder pressure, peak heat release rate and ignition delay and emissions such as UBHC, smoke opacity and NOx are reported here. From the experimental investigations it is observed that IOP 220bar and IT 26deg. bTDC showed better performance for all the test fuels. On the other hand, the performance, combustion and emission characteristics of B20 blend fueled direct injection compression ignition engine performed better for entire load range of operation. At higher loads with IOP 220bar and IT 26deg. bTDC emissions such as smoke opacity and UBHC were observed to be lower compared to other IOPs and ITs. But, NOx emission at retard IT 20deg. bTDC was very low compared to other two ITs. BTE of blend B20 fueled compression ignition engine has increased by 1.01% when operated with IOP 220bar at IT 23deg. bTDC and 1.34% with IT 26deg. bTDC at IOP 200bar. On other hand blend B20 fueled direct injection compression ignition engine showed better performance with reasonable higher brake thermal efficiency and lower BSEC, better combustion and emission when compared to biodiesel (B100) and diesel fuel.Item Combustion, performance, and tail pipe emissions of common rail diesel engine fueled with waste plastic oil-diesel blends(American Society of Mechanical Engineers (ASME) infocentral@asme.org, 2018) Lamani, V.T.; Yadav, A.K.; Kumar, G.N.The demand for plastic is eternally growing in urban areas and producing enormous quantity of plastic waste. The management and disposal of plastic waste have become a major concern worldwide. The awareness of waste to energy retrieval is one of the promising modes used for the treatment of the waste plastic. The present investigation evaluates the prospective use of waste plastic oil (WPO) as an alternative fuel for diesel engine. Different blends (WPO0, WPO30, and WPO50) with diesel are prepared on a volume basis and the engine is operated. Experiments are conducted for various injection timings (9 deg, 12 deg, 15 deg, and 18 deg BTDC) and for different exhaust gas recirculation (EGR) rates (0%, 10%, 15%, and 20%) at 100 MPa injection pressure. Combustion, performance, and tail pipe emissions of common rail direct injection (CRDI) engine are studied. The NOx, CO, and Soot emissions for waste plastic oil-diesel blends are found more than neat diesel. To reduce the NOx, EGR is employed, which results in reduction of NOx considerably, whereas other emissions, i.e., CO and Soot, get increased with increase in EGR rates. Soot for WPO-diesel blends is higher because of aromatic compounds present in plastic oils. Brake thermal efficiency (BTE) of blends is found to be higher compared to diesel. © 2018 by ASME.Item Experimental studies on cyclic variations in a single cylinder diesel engine fuelled with raw biogas by dual mode of operation(Elsevier Ltd, 2020) Jagadish, C.; Gumtapure, V.In this research work, cycle-by-cycle variations of a single cylinder, diesel engine operated with raw biogas is investigated. The biogas used to run the engine is obtained from food waste and as the composition of 88.10%-CH4 + 11.895%-CO2. To study the combustion characteristics, the naturally aspirated diesel engine is converted into dual mode by inducting the biogas into the intake manifold for different proportions from BG20 to BG60 with a step of 10% is mixed with air (i.e. BG60-60% of biogas by mass) respectively. Combustion parameters are measured and recorded by the means of the data acquisition system (DAQ) for 100 combustion cycle. By determining the parameters such as standard deviation, coefficient of variation and return map, the cycle variability is analyzed. From the experimental result, it is observed that as the engine is operated at higher loads and as the biogas is increased from BG20 to BG60 the cyclic variations for maximum cylinder pressure (Pmax) and indicated mean effective pressure (IMEP) increases. Coefficient of variation of Pmax for BG20 and BG40 is lower by 2.3% and 11.98% as compared to diesel. From time return map, BG40 showed good combustion stability and lesser NOx emission compared to diesel. © 2020 Elsevier LtdItem Experimental investigation of methane-enriched biogas in a single cylinder diesel engine by the dual fuel mode(Taylor and Francis Ltd., 2022) Chandrashekar, J.; Gumtapure, V.In this experimental work characteristic such as performance, combustion and emission of a single cylinder, four-stroke constant speed, direct injection, water-cooled diesel engine is investigated. The engine is operated by dual fuel mode using methane-enriched biogas (88.10%-CH4 + 11.89%-CO2) obtained from the food waste. Biogas (BG) is inducted into the engine at intake manifold with various mixtures like BG20, BG30 and BG40 mixed with air (i.e. BG40-40% of CH4 by mass respectively) at actual injection timing of 27.5° before top dead centre (bTDC) for different loads. The performance, combustion and emission characteristics of the engine operated by dual fuel mode were experimentally investigated, and compared with respect to diesel. By observing the experimental results, BG40 was optimized on the basis of lesser emissions and improved performance. BG40 showed lesser brake thermal efficiency and higher brake specific energy consumption than BG20 and BG30 for all loads. On the other hand, BG40 showed lower BTE by 15.5% and 15.62% compared to diesel at 3/4th and full load. Whereas the cylinder peak pressure for BG40 is higher than diesel by 5.36% and the net heat release rate is 14.9% higher than the diesel at full load. BG40 emitted higher carbon monoxide (CO) emissions than diesel by 5% at full load. The nitrogen oxide (NOx) emission for BG40 was lesser by 26.60% than diesel at full load, whereas the soot emission was 22.71% lower than diesel at full load respectively. © 2022 Taylor & Francis Group, LLC.Item Experimental Study on the Effect of Injection Timing on a Dual Fuel Diesel Engine Operated With Biogas Derived From Food Waste(American Society of Mechanical Engineers (ASME), 2022) Chandrashekar, J.; Gumtapure, V.The present work emphasizes the effects of injection timing on the characteristics of a 5.2-kW powered four-stroke diesel engine using biogas and its heat loss analysis. The biogas is obtained from food waste consisting of methane (CH4)-88.1% and carbon dioxide (CO2)-11.8% as the composition. The biogas (BG) is selected by mass basis ranging from 20% to 60% with 10% increments and is used to operate the engine by dual-fuel mode. The effect of three injection timings such as 25.5 deg (retarded), 27.5 deg (actual), and 29.5 deg (advanced) before top-dead center (bTDC) under dual-mode operation to enhance the properties of the engine is studied, and the results are compared with diesel mode at actual injection timing. Maximum brake thermal efficiency of 30.1% was observed for BG20 operated at 29.5-deg bTDC injection timing (IT). The dual mode operated at the injection timing of 29.5-deg bTDC showed an increase in cylinder pressure compared to diesel by 11.9% at full load conditions, whereas carbon monoxide emission was lower by 5.2% at 29.5-deg bTDC IT than diesel, and nitrogen oxide emission was lower at 25.5 deg bTDC IT than diesel mode by 45%. Besides, at 75% engine load, the least amount of heat losses was observed for BG50 exhibiting effective conversion of fuel energy into equivalent work higher than that of diesel by 2.2%, respectively. © © 2022 by ASME.Item Effect of DEE added Karanja biodiesel fuel on the performance, combustion and emission characteristics of CI engine under variable injection timing and engine load(Taylor and Francis Ltd., 2023) Wogasso Wodajo, A.; Yadav, A.K.; Gottekere Narayanappa, K.The higher density and viscosity of biodiesel reduce the engine's performance due to poor atomisation. The present study aims to investigate the effect of DEE and injection time on engine characteristics fueled with KME-diesel blends. For this purpose, single cylinder CI engine is used. The injection timing is advanced and retarded by 2° from the base injection timing (27° bTDC), and the load is varied from 0% to 100%. The addition of DEE to the blends results in a reduction of density and viscosity. At 29° bTDC, the brake thermal efficiency for 5% DEE is increased by 3.1% compared to a blend without DEE at full load. For 5% DEE, compared to 27° bTDC, 29° bTDC reduces the HC and CO emission by 4.5% and 42.8%, respectively at full load. It is concluded that the 5% DEE operating at 29° bTDC improves the engine's performance with a small rise in NOX emission. Highlights: DEE added biodiesel blend has lower viscosity and density than biodiesel. 5% DEE addition in biodiesel blend at advanced injection timing improves BTE and reduces emission. Lower in-cylinder temperature is achieved due to higher latent heat of evaporation. The CO and HC emissions for B25DE5 at 29° bTDC are reduced by 4.5% and 42.8% than 27° bTDC at full load. At advanced injection timing NOX emission for 5% DEE addition increased by 2.7% than 27° bTDC. © 2022 Informa UK Limited, trading as Taylor & Francis Group.Item Effect of fuel injection timing on engine characteristics with an equal volume of 1-heptanol/diesel blend in a CRDI CI engine(Elsevier B.V., 2025) Bhumula, K.B.; Kumar, G.N.1-Heptanol (C7H15OH) is a superior and eco-friendly alternative to diesel fuel derived from renewable biomass to address environmental concerns and mitigate fossil fuel depletion. Testing in this research involved using a single-cylinder, four-stroke CRDI diesel engine. The engine ran at a constant speed of 1500 rpm and was fueled with a blend of 50 % 1-heptanol/diesel by volume. The research focused on examining the impact of different injection timings (21°, 23°, and 25 °CA bTDC) specifically, retarded, standard, and advanced timings, as well as varying engine loads of 4, 8 and 12 kg on engine performance, combustion efficiency, and emissions. Experimental test results showed that blending 1-heptanol/diesel fuel led to a substantial decrease in NOx emissions and smoke opacity, which were reduced by 27 % and 26 %, respectively. However, when using a 50 % 1-heptanol/diesel blend and testing with advanced injection timing, there was a 2.26 % decrease in BTE and a 5.1 % increase in BSFC compared to pure diesel. The injection timing advancement improves premixed combustion but increases HC and CO emissions. Research suggests a 50 % blend of 1-Heptanol as a promising renewable fuel for diesel engines, with slight modifications. © 2025 The Authors