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Item Technical aspects of biodiesel and its oxidation stability(2009) Kapilan, N.; Ashok Babu, T.P.; Reddy, R.P.Biodiesel is a clean burning alternative renewable fuel made from natural renewable sources. It is defined as mono-alkyl esters of long chain fatty acids derived from vegetable oils or animal fats, which conform to ASTM specifications for use in diesel engines. Biodiesel present a very promising alternative fuel to diesel oil and properties of this oil offer the advantage of immediate substitution in existing diesel engines with little or no modifications at all. But one of the major technical problems associated with the biodiesel is its susceptibility to oxidation, which can cause the fuel to become acidic and to form insoluble gums and sediments that can plug fuel filters. This is due to the unsaturated fatty acid chains and the presence of the double bond in the molecule, which produce a high level of reactivity with the oxygen, especially when it placed in contact with air. The oxidation of fatty acid chains is a complex process that proceeds by a variety of mechanisms. The various other factors influence the oxidation process of biodiesel includes light, temperature, extraneous materials, peroxides, size of the surface area between biodiesel and air. One of the methods of improving biodiesel oxidative stability includes the deliberate addition of antioxidants or modification of the fatty ester profile. This article discusses the technical aspects of biodiesel and its oxidation stability.Item Comparison of performance of biodiesels of mahua oil and gingili oil in dual fuel engine(Serbian Society of Heat Transfer Engineers, 2008) Nadar, K.N.; Reddy, R.P.; Anjuri, E.R.In this work, an experimental work was carried out to compare the performance of biodiesels made from non edible mahua oil and edible gingili oil in dual fuel engine. A single cylinder diesel engine was modified to work in dual fuel mode and liquefied petroleum gas was used as primary fuel. Biodiesel was prepared by transesterification process and mahua oil methyl ester (MOME) and gingili oil methyl ester (GOME) were used as pilot fuels. The viscosity of MOME is slightly higher than GOME. The dualfuel engine runs smoothly with MOME and GOME. The test results show that the performance of the MOME is close to GOME, at the pilot fuel quantity of 0.45 kg/h and at the advanced injection timing of 30 deg bTDC. Also it is observed that the smoke, carbon monoxide and unburnt hydro carbon emissions of GOME lower than the MOME. But the GOME results in slightly higher NOx emissions. From the experimental results it is concluded that the biodiesel made from mahua oil can be used as a substitute for diesel in dual fuel engine.Item Evaluation of methyl esters of mahua oil (mahua indica) as diesel fuel(2008) Kapilan, N.; Reddy, R.P.There is increasing interest in India for suitable alternative fuels that are environment friendly. This search has led to mahua oil (MO) as one alternative for diesel fuel in India. Mahua oil methyl esters (MOME) were prepared by transesterification using potassium hydroxide (KOH) as catalyst and nuclear magnetic resonance (NMR) testing was done to determine the conversion of vegetable oil to biodiesel (MOME). The properties of MOME were close to those of diesel oil. Engine testing was conducted using a single-cylinder 4-stroke direct-injection, constant-speed compression-ignition diesel engine using MO, MOME and B20 as fuels. The engine ran smoothly with MOME and B20, but heavy smoke emissions were observed when MO was used as fuel. © 2007 AOCS.Item Experimental investigation of esters of mahua oil as an alternative fuel for dual fuel engine(2008) Reddy, P.B.; Kapilan, N.; Reddy, R.P.In the present work, an attempt was made to use methyl ester of mahua oil (MEMO) as substitute for dieselin dual fuel engine. A four stroke single cylinder engine was modified to work in dual fuel mode. From the test results, it was observed that the MEMO could be used as pilot fuel in dual fuel engine. At lower loads, diesel gave higher brake thermal efficiency. But at higher loads, biodiesel resulted in brake thermal efficiency comparable with diesel and lower smoke and oxides of nitrogen emissions. From the test results, it was concluded that MEMO could be used as a substitute for diesel in dual fuel engine.Item 6BTA 5.9 G2-1 Cummins engine performance and emission tests using methyl ester mahua (Madhuca indica) oil/diesel blends(2009) Godiganur, S.; Suryanarayana Murthy, C.H.; Reddy, R.P.Neat mahua oil poses some problems when subjected to prolonged usage in CI engine. The transesterification of mahua oil can reduce these problems. The use of biodiesel fuel as substitute for conventional petroleum fuel in heavy-duty diesel engine is receiving an increasing amount of attention. This interest is based on the properties of bio-diesel including the fact that it is produced from a renewable resource, its biodegradability and potential to exhaust emissions. A Cummins 6BTA 5.9 G2- 1, 158 HP rated power, turbocharged, DI, water cooled diesel engine was run on diesel, methyl ester of mahua oil and its blends at constant speed of 1500 rpm under variable load conditions. The volumetric blending ratios of biodiesel with conventional diesel fuel were set at 0, 20, 40, 60, and 100. Engine performance (brake specific fuel consumption, brake specific energy consumption, thermal efficiency and exhaust gas temperature) and emissions (CO, HC and NOx) were measured to evaluate and compute the behavior of the diesel engine running on biodiesel. The results indicate that with the increase of biodiesel in the blends CO, HC reduces significantly, fuel consumption and NOx emission of biodiesel increases slightly compared with diesel. Brake specific energy consumption decreases and thermal efficiency of engine slightly increases when operating on 20% biodiesel than that operating on diesel. © 2008 Elsevier Ltd. All rights reserved.Item Characterization and effect of using Mahua oil biodiesel as fuel in compression ignition engine(2009) Kapilan, N.; Ashok Babu, T.P.; Reddy, R.P.There is an increasing interest in India, to search for suitable alternative fuels that are environment friendly. This led to the choice of Mahua Oil (MO) as one of the main alternative fuels to diesel. In this investigation, Mahua Oil Biodiesel (MOB) and its blend with diesel were used as fuel in a single cylinder, direct injection and compression ignition engine. The MOB was prepared from MO by transesterification using methanol and potassium hydroxide. The fuel properties of MOB are close to the diesel and confirm to the ASTM standards. From the engine test analysis, it was observed that the MOB, B5 and B20 blend results in lower CO, HC and smoke emissions as compared to diesel. But the B5 and B20 blends results in higher efficiency as compared to MOB. Hence MOB or blends of MOB and diesel (B5 or B20) can be used as a substitute for diesel in diesel engines used in transportation as well as in the agriculture sector. © 2009 Science Press, Institute of Engineering Thermophysics, CAS and Springer Berlin Heidelberg.Item The effect of karanja oil methyl ester on Kirloskar HA394DI diesel engine performance and exhaust emissions(Serbian Society of Heat Transfer Engineers, 2010) Godiganur, S.; Suryanarayana Murthy, Ch.; Reddy, R.P.Biofuels are being investigated as potential substitutes for current high pollutant fuels obtained from the conventional sources. The primary problem associated with using straight vegetable oil as fuel in a compression ignition engine is caused by viscosity. The process of transesterifiction of vegetable oil with methyl alcohol provides a significant reduction in viscosity, thereby enhancing the physical properties of vegetable oil. The Kirloskar HA394 compression ignition, multi cylinder diesel engine does not require any modification to replace diesel by karanja methyl ester. Biodiesel can be used in its pure form or can be blended with diesel to form different blends. The purpose of this research was to evaluate the potential of karanja oil methyl ester and its blend with diesel from 20% to 80% by volume. Engine performance and exhaust emissions were investigated and compared with the ordinary diesel fuel in a diesel engine. The experimental results show that the engine power of the mixture is closed to the values obtained from diesel fuel and the amounts of exhaust emissions are lower than those of diesel fuel. Hence, it is seen that the blend of karanja ester and diesel fuel can be used as an alternative successfully in a diesel engine without any modification and in terms of emission parameters; it is an environmental friendly 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 Performance characteristics of a dual fuel engine operated with Mahua biodiesel and liquefied petroleum gas(ASTM International, 2011) Kapilan, N.; Ashok Babu, T.P.; Reddy, R.P.Fuel crisis because of dramatic increase in vehicular population and environmental concerns have renewed the interest of the scientific community to look for alternative fuels of bio-origin such as vegetable oils and ethanol. India is looking at biodiesel derived from Mahua oil (MO), as one of the renewable alternative fuels for compression ignition (CI) engine. Although MO biodiesel (MOB) has several advantages over fossil diesel, in the present scenario, the use of biodiesel is restricted due to its high cost. In India, liquefied petroleum gas (LPG) is easily available and is one of the cheapest gaseous fuels. Hence, use of LPG to fuel a CI engine along with MOB seems to be an option for substitution of fossil diesel. In the present work, LPG, which was fumigated along with the air and biodiesel was admitted into the engine cylinder through conventional fueling device as an igniter. A single cylinder CI engine was modified to work in dual fuel mode and engine tests were carried out at rated speed under variable load conditions. The performance of the engine in dual fuel mode was compared with the diesel. The dual fuel operation results in thermal efficiency close to the diesel and also reduces the NOx and smoke emissions significantly. From the experimental results, we concluded that biodiesel in dual fuel mode with cheaper gaseous fuel induction is an option for reducing the operating cost of the biodiesel fuelled CI engine. Copyright ©2011 by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959.Item Performance characteristics of a dual fuel engine operatedwith mahua biodiesel and liquefied petroleum gas(2011) Kapilan, N.; Ashok Babu, T.P.A.; Reddy, R.P.Fuel crisis because of dramatic increase in vehicular population and environmental concerns have renewed the interest of the scientific community to look for alternative fuels of bio-origin such as vegetable oils and ethanol. India is looking at biodiesel derived from Mahua oil (MO), as one of the renewable alternative fuels for compression ignition (CI) engine. Although MO biodiesel (MOB) has several advantages over fossil diesel, in the present scenario, the use of biodiesel is restricted due to its high cost. In India, liquefied petroleum gas (LPG) is easily available and is one of the cheapest gaseous fuels. Hence, use of LPG to fuel a CI engine along with MOB seems to be an option for substitution of fossil diesel. In the present work, LPG, which was fumigated along with the air and biodiesel was admitted into the engine cylinder through conventional fueling device as an igniter. A single cylinder CI engine was modified to work in dual fuel mode and engine tests were carried out at rated speed under variable load conditions. The performance of the engine in dual fuel mode was compared with the diesel. The dual fuel operation results in thermal efficiency close to the diesel and also reduces the NOx and smoke emissions significantly. From the experimental results, we concluded that biodiesel in dual fuel mode with cheaper gaseous fuel induction is an option for reducing the operating cost of the biodiesel fuelled CI engine. Copyright © 2011 by ASTM International.