2. Conference Papers
Permanent URI for this collectionhttps://idr.nitk.ac.in/handle/1/7
Browse
11 results
Search Results
Item Performance and emission studies on the effect of injection timing and diesel replacement on a 4-S LPG-Diesel Dual-Fuel Engine(2003) Sudhir, C.V.; Desai, V.; Kumar, S.Y.; Mohanan, P.Reducing the emissions and fuel consumption are no longer future goals; instead they are the demands of the day. People are concerned about rising fuel costs and effects of emissions on the environment. Diesel engines are the major contributors to the increased levels of pollutants. In the present work an attempt is made for effective utilization of diesel engine with reduced fuel consumption, smoke density and NOx emissions. This is achieved by some minor modifications in diesel engine so as to run it as LPG-Diesel Dual-fuel engine with LPG (Liquefied Petroleum Gas) (70% Butane + 30% Propane) induction at air intake. The important aspect of LPG-Diesel dual-fuel engine is that, it shows significant reduction in smoke density, NOx emission and improved brake thermal efficiency with reduced energy consumption. An existing 4-S, single cylinder, naturally aspirated, water-cooled, direct injection, C.I. 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 was studied. The optimal diesel replacement pertaining to the maximum allowable LPG flow limits could be assessed with these experiments. The influence of the injection timing variation on the engine performance and smoke density was analyzed form the experimental results. It was observed that beyond half load operation of the dual-fuel engine, thermal efficiency increased with diesel replacement, and at full load up to 4% improvement was observed compared to full diesel operation. There was drastic reduction in NOx emissions (up to40- 60 %) for the entire load range, except near full load where NOx increased (by38%) beyond full diesel value at normal injection timing. At full load reduction in smoke density up to 40% to 60% was observed compared to full diesel operation. At advance injection timing of 30�btdc the performance of the dual fuel engine was better with lower smoke density, while the NOx emission was found to be higher. Copyright � 2003 SAE International.Item Performance and emission studies of diesel engine using diethyl ether as oxygenated fuel additive(2008) Kapilan, N.; Mohanan, P.; Reddy, R.P.There is currently interest in finding means to improve motor vehicle fuel economy while complying with emissions regulations. Fuel additives have been widely reported to improve engine cleanliness and performance with diesel engines. Diethyl Ether (DEE) has high octane number and compatible with current vehicle technology and fuel infrastructure. Although DEE has long been known as a cold start aid for engines, knowledge about using DEE for other operations, such as significant component of a blend or additive is limited. In this present work, experiments were conducted to study the influence of DEE on the performance and emissions of a 4-S direct injection diesel engine. From the experimental results, it is observed that the addition of DEE to diesel fuel improves the performance of the diesel engine. A slight improvement in the thermal efficiency and reduction in smoke, carbon moNOxide and hydro carbon emissions were observed with B5 Blend (5 % DEE + 95 % Diesel). � 2008 SAE International.Item Optimizing brake specific fuel consumption of low-NOx, emission standard compliant CI engines, by tuning engine parameters(2009) Menon, P.G.; Mohanan, P.Reducing NOx from about 10.7 g/bhp-hr to about 4.5 g/bhp-hr caused a 6% loss in fuel economy in engine designs of the late 1980s and early 1990s [1]. Reasons for this loss in fuel economy are attributed to the loss in peak combustion pressure due to the delayed fuel injection among other technologies used in NOx control that leads to reduced cycle work. To compensate for the loss of work output, more fuel is provided to produce the desired work and leading to increased Brake Specific Fuel Consumption (BSFC). To optimize BSFC in Automobile Diesel Engines using Low-NOx technologies like fuel injection retard and fuel injection rate shaping, to stay within emission norms, a transient model was developed in Matlab/Simulink to control and optimize the various engine parameters contributing to the production of NOx and to realistically determine an ideal operating point for the functioning of an engine of a given configuration keeping in mind NOx production as well as BSFC. � 2009 Combustion Institute. All rights reserved.Item Experimental investigations on a compressed natural gas operated dual fuel engine(2005) Kapilan, N.; Somayaji, C.; Mohanan, P.; Reddy, R.P.In the present work, an attempt has been made for the effective utilization of Compressed Natural Gas (CNG) in diesel engine. A four stroke, single cylinder diesel engine was modified to work on dual fuel mode. The effect of CNG flow rate and Exhaust Gas Recirclulation (EGR) on the performance and emissions of the dual fuel engine was studied. The variables considered for the tests were different CNG flow rates (0.2, 0.3, 0.4, 0.5, 0.6 and 0.7 kg/hr), EGR (0%, 4.28%, 6.63 % and 8.12%) and loads (25%, 50%, 75% and 100 % of full load). From the test results, it was observed that the EGR rate of 4.28 % results in better brake thermal efficiency and lower CO and NOx emissions than other ERG rates at 25%, 50% and 75% of full loads. At full load, EGR rate of 8.12 % results in higher brake thermal efficiency and lower NOx emissions. Copyright � 2005by ASME.Item COMBUSTION and EMISSION CHARACTERISTICS of DIESEL, B100 and B20 FUEL on A THERMAL BARRIER COATING on PISTON CROWN in DIRECT INJECTION C.I. ENGINE at OPTIMUM IOP and IT(2009) Dhananjaya, D.A.; Mohanan, P.; Sudhir, C.V.The objective of this study is to investigate the performance, combustion and emission characteristics of Jatropha biodiesel and its blend fueled in standard CI engine (without coating piston crown) and thermal barrier coating (with coating of piston crown) CI engine at optimum injector opening pressure (IOP) and injection timing (IT). Tests were performed on a single cylinder, four stroke, direct injection, water cooled, CI engine whose piston crown were coated with a 300?m thickness of zirconium oxide over a 150?m thickness of nickel chromium and aluminum oxide bond coat at optimum IOP and IT (220 bar and 26� btdc). The working conditions for the standard and thermal barrier coating of piston crown CI engine were kept exactly the same to ensure a realistic comparison between the two configurations of the engine. During this investigation, both the engine was fueled with the diesel fuel, biodiesel and its blend of biodiesel and neat diesel fuel in proportions of 20% biodiesel and 80% diesel fuel which are generally called of B20 fuel. In this work various performance parameters such as brake thermal efficiency, brake specific energy consumption, combustion characteristics such as peak cylinder pressure, peak heat release rate, ignition delay and emission parameter such as UBHC, smoke opacity and NOx under varying load conditions are studied and recorded. The test results indicate that performance, combustion and emission characteristics of the B20 fueled with thermal barrier coating CI engine for all load range has improved. At full load at B20 fuel, emissions such as UBHC and smoke opacity were observed to be lower compared to the standard CI engine. The thermal efficiency and specific energy consumption of B20 fueled at full load conditions of thermal barrier coating CI engine has increased approximately by 1.96% and decreased approximately by 4.2% respectively when compared to standard CI engine. � Copyright 2009 SAE International.Item Characterization and performance study of biodiesel from waste cooking oil in a direct injection diesel engine(2009) Mohanan, P.Analysis of different samples of Waste Cooking Oil (WCO) to assess their suitability as raw material for the production of biodiesel through transesterification reaction is carried out. The degradation of cooking oil is mainly due to the thermal oxidation reaction and hydrolysis reaction during frying. Acid-alkali and alkali methods are employed for transesterification reaction for producing biodiesel from thermally degraded WCO obtained under controlled laboratory conditions. The work focuses also the determination of catalyst required for the transesterification process and the correlation with acid value and Free Fatty Acid (FFA) content of the WCO. It was established that acid-alkali method gave better physiochemical properties compared to alkali method and B20 blend obtained by this method has shown comparable performance and improved emission characteristics with diesel fuel when tested in a compression ignition (C.I) engine. � 2009 Combustion Institute. All rights reserved.Item EFFECT of INJECTION PRESSURE and INJECTION TIMING on A SEMI-ADIABATIC CI ENGINE FUELED with BLENDS of JATROPHA OIL METHYL ESTERS(2008) Dhananjaya, D.A.; Mohanan, P.; Sudhir, C.V.A naturally aspirated four stroke single cylinder CI engine was modified to run as semi-adiabatic CI engine. The effect of different injection pressure and injection timing of a standard and semi-adiabatic engine on the combustion performance and emission characteristics of jatropha oil methyl ester (JOME) and its volume blends with diesel is presented in this paper. Performance of the CI engine was evaluated in terms of brake specific energy consumption, brake thermal efficiency, exhaust gas temperature and exhaust gas composition. Five different volume blends of JOME viz. B5, B10, B15, B20 and B25 was used for the combustion studies at various injection pressures viz. 180, 200, 220 and 240 bar and also at different injection timings i.e. 22�,27� and 32� btdc. This experimental study focused on deriving an optimal injection timing and pressure for the satisfactory operation of JOME blends in a semi-adiabatic engine. The study revealed that acceptable brake thermal efficiency, brake specific energy consumption and emission characteristics of the engine were obtained up to B25 of JOME. At injector opening pressure of 220bar, B20 blend fuel showed better combustion performance and lower exhaust emissions compared to other blends and diesel fuel. At this combination the specific energy consumption were 11.67 MJ/kW-hr and brake thermal efficiency were 30.87% for a semi-adiabatic engine, while the same for standard engine (Non Coated), was found to be 12.60 MJ/kW-hr and 28.67% respectively. At full load, with injection timing of 32� btdc and with B20 JOME blend fuel showed the specific energy consumption of 11.52 MJ/kW-hr and thermal efficiency of 31.72% for semi-adiabatic engine, while for standard engine same was found to be 12.21 MJ/kW-hr and 29.28% respectively. This infers that the semi-adiabatic engine showed better combustion than the standard engine. � 2008 SAE International.Item Effect of bio-diesel (B20) on performance and emissions of optimum injector opening pressure operating at different injection timings of a semi-adiabatic engine(2009) Dhananjaya, D.A.; Sudhir, C.V.; Mohanan, P.This study was carried out to investigate the performance and emission characteristics of jatropha methyl ester oil and its blend B20 with mineral diesel on a single-cylinder four-stroke direct injection water cooled diesel engine operated at optimum IOP 220bar at different injection timing of standard and semi-adiabatic engine. The results of comparative measures of brake thermal efficiency, smoke and NOx have been presented and discussed on both the types of engines. The engine performance in terms of higher thermal efficiency and lower emissions of B20 blend fuel operation was observed and compared with jatropha methyl ester oil and mineral diesel fuel of 20o bTDC, 23o bTDC and 26o bTDC of standard and semi-adiabatic engine. � 2009 Combustion Institute. All rights reserved.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.