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Combustion and emission characteristics of a diesel engine fuelled with jatropha and diesel oil blends  [PDF]
Elango Thangavelu,Senthilkumar Thamilkolundhu
Thermal Science , 2011, DOI: 10.2298/tsci100614088e
Abstract: The depletion of oil resources as well as the stringent environmental regulations has led to the development of alternate energy sources. In this work the combustion, performance and emission characteristics of a single cylinder diesel engine when fuelled with blends of jatropha and diesel oil are evaluated. Experiments were conducted with different blends of jatropha oil and diesel at various loads. The peak pressures of all the blends at full load are slightly lower than the base diesel. There is an increase in the ignition delay with biodiesel because of its high viscosity and density. The results show that the brake thermal efficiency of diesel is higher at all loads followed by blends of jatropha oil and diesel. The maximum brake thermal efficiency and minimum specific fuel consumption were found for blends up to B20. The specific fuel consumption, exhaust gas temperature, smoke opacity and NOx were comparatively higher. However there is an appreciable decrease in HC and CO2 emissions while the decrease in CO emission is marginal. It was observed that the combustion characteristics of the blends of esterified jatropha oil with diesel followed closely with that of the base line diesel.
Investigations on Performance and Emission Characteristics of Diesel Engine with Biodiesel (Jatropha Oil) and Its Blends  [PDF]
Amar Pandhare,Atul Padalkar
Journal of Renewable Energy , 2013, DOI: 10.1155/2013/163829
Abstract: This paper presents the performance of biodiesel blends in a single-cylinder water-cooled diesel engine. All experiments were carried out at constant speed 1500?rpm and the biodiesel blends were varied from B10 to B100. The engine was equipped with variable compressions ratio (VCR) mechanism. For 100% Jatropha biodiesel, the maximum fuel consumption was 15% higher than that of diesel fuel. The brake thermal efficiency for biodiesel and its blends was found to be slightly higher than that of diesel at various load conditions. The increase in specific fuel consumption ranged from 2.75% to 15% for B10 to B100 fuels. The exhaust gas temperature increased with increased biodiesel blend. The highest exhaust gas temperature observed was 430°C with biodiesel for load conditions 1.5?kW, 2.5?kW, and 3.5?kW, where as for diesel the maximum exhaust gas temperature was 440°C. The CO2 emission from the biodiesel fuelled engine was higher by 25% than diesel fuel at full load. The CO emissions were lower with Jatropha by 15%, 13%, and 13% at 1.5?kW, 2.5?kW, and 3.5?kW load conditions, respectively. The emissions were higher by 16%, 19%, and 20% at 1.5?kW, 2.5?kW, and 3.5?kW than that of the diesel, respectively. 1. Introduction Diesel engines have provided power units for road transportation systems, ships, railway locomotives, equipment used for farming, construction, and in almost every type of industry due to its fuel efficiency and durability. However, Diesel engines are the major sources of and particulate matter emissions which are environmental concerns. For automotive industry the reduction of and PM emission is the most important task. National governments are imposing stringent emissions on automotive sector to reduce and PM emissions. Also global house warming gases (GHG) are going to receive more focus from future autosector. Therefore, the stringent emission regulation requirements give a major challenge to comply emission targets while maintaining its performance, drivability, durability, and fuel economy. The use of alternative fuels for internal combustion engines has attracted a great deal of attention due to fossil fuel crisis and also GHG impact. Alternative fuels should be easily available, environment friendly, and technoeconomically competitive. Successful alternative fuel should fulfill environmental and energy security needs without sacrificing engine operating performance [1]. Renewable resources offer the opportunity to tap local resources and reduce dependency on fossil energy resources. Most biodiesel oils, particularly of the nonedible type
The effect of EGR rates on NOX and smoke emissions of an IDI diesel engine fuelled with Jatropha biodiesel blends  [PDF]
M. Gomaa, A.J. Alimin, K.A. Kamarudin
International Journal of Energy and Environment , 2011,
Abstract: The depletion of fossil fuels and the worst impact on environmental pollution caused of their burning have led to the search for renewable clean energies. Nowadays, there are many sources of renewable energy. Biodiesel is just one source, but a very important one. Biodiesel has been known as an attractive alternative fuel although biodiesel produced from edible oil is very expensive than conventional diesel. Therefore, the uses of biodiesel produced from non-edible oils are much better option. Currently Jatropha biodiesel (JBD) is receiving attention as an alternative fuel for diesel engine. However, previous studies have reported that combustion of JBD emitted higher nitrogen oxides (NOX), while hydrocarbon (HC) and smoke emissions were lower than conventional diesel fuel. Exhaust gas recirculation (EGR) is one of the techniques being used to reduce NOX emission from diesel engines; because it decreases both flame temperature and oxygen concentration in the combustion chamber. Some studies succeeded to reduce NOX emission from biodiesel fuelled engines using EGR; but they observed increase in smoke emission with increasing engine load and EGR rate. The aim of the present work is to investigate the effect of EGR on an indirect injection (IDI) diesel engine fuelled with JBD blends in order to reduce NOX and smoke emissions. A 4-cylinder, water-cooled, turbocharged, IDI diesel engine was used for investigation. Smoke, NOX, carbon monoxide (CO) and carbon dioxide (CO2) emissions were recorded and various engine performance parameters were also evaluated. The results showed that, at 5% EGR with JB5, both NOX and smoke opacity were reduced by 27% and 17% respectively. Furthermore, JB20 along with 10% EGR was also able to reduce both NOX and smoke emission by 36% and 31%, respectively compared to diesel fuel without EGR.
Study of oxidation stability of Jatropha curcas biodiesel/ diesel blends  [PDF]
Siddharth Jain, M.P. Sharma
International Journal of Energy and Environment , 2011,
Abstract: Biodiesel production is undergoing rapid technological reforms in industries and academia. This has become more obvious and relevant since the recent increase in the petroleum prices and the growing awareness relating to the environmental consequences of the fuel overdependency. However, the possibilities of production of biodiesel from edible oil resources in India is almost impossible, as primary need is to first meet the demand of edible oil that is already imported therefore it is essential to explore non-edible seed oils, like Jatropha curcas and Pongamia as biodiesel raw materials. The oxidation stability of biodiesel from Jatropha curcas oil is very poor. Therefore the aim of the present paper is to study the oxidation stability of Jatropha curcas biodiesel/ diesel blend. Also the effectiveness of various antioxidants is checked with respect to various blends of biodiesel with diesel.
Diesel Internal Combustion Engine Emissions Measurements for Methanol-Based and Ethanol-Based Biodiesel Blends  [PDF]
Charalambos A. Chasos,George N. Karagiorgis,Chris N. Christodoulou
Conference Papers in Science , 2013, DOI: 10.1155/2013/162312
Abstract: There is a recent interest for the utilisation of renewable and alternative fuel, which is regulated by the European Union, that currently imposes a lower limit of 7% by volume of biodiesel fuel blend in diesel fuel. The biodiesel physical characteristics, as well as the percentage of biodiesel blend in diesel fuel, affect the injector nozzle flow, the spray characteristics, the resulting air/fuel mixture, and subsequently the combustion quality and emissions, as well as the overall engine performance. In the present study, two different types of pure biodiesel fuel, namely, methanol-based biodiesel and ethanol-based biodiesel, were produced in the laboratory of Frederick University by chemical processing of raw materials. The two biodiesel fuels were used for blending pure diesel fuel at various percentages. The blends were used for smoke emissions measurements of a diesel internal combustion engine at increasing engine speed and for increasing engine temperatures. From the experimental investigations it was found that ethanol-based biodiesel blends result in higher smoke emissions than pure diesel fuel, while methanol-based biodiesel blends smoke emissions are lower compared to pure diesel fuel. 1. Introduction There is recent interest for the utilisation of renewable and alternative fuels by the European Union (EU), which is regulated by Directive 2009/30/EC. For the usage of biodiesel blends, a lower limit of 7% by volume biodiesel fuel blend in diesel fuel is currently imposed. The specifications of biodiesel fuels which can be used for blending diesel fuel are defined by the European standard EN 14214 [1]. The physical properties of biodiesel affect the diesel blends, and the range of density, viscosity, and flash point of biodiesel are specified in EN 14214. However, other physical properties of diesel blends including the surface tension coefficient, the fuel vapour pressure, the boiling point, and the latent heat of evaporation also affect the injected fuel spray characteristics, the resulting air/fuel mixing, combustion, and the emissions of diesel internal combustion engines (ICE), as well as the engine overall performance. Biodiesel is mainly produced from oilseed crops and other raw materials [2]. Biodiesel fuels can be produced from rapeseed via cold pressing/extraction and transesterification, known as fatty acid methyl ester (FAME) [3], and are known as first generation biofuels. For second generation biodiesel fuels known as hydrotreated biodiesel, hydrotreatment technologies are used for vegetable oils and animal fat materials [3].
An experimental investigation of performance and exhaust emission of a diesel engine fuelled with Jatropha biodiesel and its blends  [PDF]
Nitin Shrivastava, S.N. Varma, Mukesh Pandey
International Journal of Energy and Environment , 2012,
Abstract: An experimental investigation has been carried out to examine the Performance parameters and exhaust emission of a diesel engine fuelled with diesel fuel, a Jatropha Biodiesel namely Jatropha oil methyl ester (JOME), its 20 percent (B20) and 50 percent (B50) blends as an alternative diesel engine fuel. JOME was prepared using Jatropha oil, methyl alcohol and potassium hydroxide as catalyst. Tests have been carried out in four cylinder direct injection diesel engine with different loading conditions. Performance parameters investigated are Brake thermal efficiency, Brake specific fuel consumption (BSFC) and Brake specific Energy consumption (BSEC), the emission parameters investigated are CO, HC, NOx, and smoke. Results showed that JOME pure or its blend both showed considerable reduction in emission except NOx. A fuel blend of 20 percent JOME showed approximately same BTE as that of neat Diesel fuel. The result showed that the Biodiesel derived from Jatropha oil Showed comparable performance and can be a good replacement to petroleum diesel.
Comparative study of macroscopic spray parameters and fuel atomization behaviour of SVO (Jatropha), its biodiesel and blends
Agarwal Avinash K.,Chaudhury Vipul,Agarwal Anuj,Shukla Pravesh C.
Thermal Science , 2013, DOI: 10.2298/tsci120306109a
Abstract: The combustion and emission characteristics of vegetable oils and derivatives are quite different from mineral diesel due to their relatively high viscosity, density and vaporisation characteristics. These properties affect the fuel spray and the interaction of the spray with air in the combustion chamber therefore it is important to analyze the spray characteristics e.g. spray tip penetration, spray cone angle, spray area and fuel atomization. Optical techniques for spray visualization and image processing are very efficient to analyse the comparative spray parameters for these fuels. Present research investigates the effect of chamber pressure on spray characteristics of Jatropha SVO (J100)/ blends (J5, J20), and Jatropha biodiesel (JB100)/ blends (JB5, JB20) vis-a-vis baseline data of mineral diesel. Experiments were performed for all these fuels/ blends injected in a constant volume spray visualisation chamber (cold chamber) at four different chamber pressure (1, 4, 7 and 9 bar respectively). It was found that J100 and JB100 have the highest spray tip penetration, cone angle and the spray area followed by J20, J5, mineral diesel and JB20, JB5, mineral diesel respectively however J20, J5 and JB20, JB5 have better atomization characteristics as compared to J100 and JB100 respectively. Cone angle was higher for biodiesel blends as compared to SVO blends at atmospheric pressure however as the chamber pressure was increased to 9 bars, it became almost equal for both fuel types. Spray parameters are found to be excellent for mineral diesel followed by Jatropha biodiesel and Jatropha oil. It was found that atomization of fuel becomes superior with increasing chamber pressure.
EXPERIMENTAL COMBUSTION ANALYSIS OF A HSDI DIESEL ENGINE FUELLED WITH PALM OIL BIODIESEL-DIESEL FUEL BLENDS
AGUDELO,JOHN; GUTIéRREZ,ELKIN; BENJUMEA,PEDRO;
DYNA , 2009,
Abstract: differences in the chemical nature between petroleum diesel fuels and vegetable oils-based fuels lead to differences in their physical properties affecting the combustion process inside the engine. in this work a detailed combustion diagnosis was applied to a turbocharged automotive diesel engine operating with neat palm oil biodiesel (pob), no. 2 diesel fuel and their blends at 20 and 50% pob by volume (b20 and b50 respectively). to isolate the fuel effect, tests were executed at constant power output without carrying out any modification of the engine or its fuel injection system. as the pob content in the blend increased, there was a slight reduction in the fuel/air equivalence ratio from 0.39 (b0) to 0.37 (b100), an advance of injection timing and of start of combustion. additionally, brake thermal efficiency, combustion duration, maximum mean temperature, temperature at exhaust valve opening and exhaust gas efficiency decreased; while the peak pressure, exergy destruction rate and specific fuel consumption increased. with diesel fuel and the blends b20 and b50 the same combustion stages were noticed. however, as a consequence of the differences pointed out, the thermal history of the process was affected. the diffusion combustion stage became larger with pob content. for b100 no premixed stage was observed.
EXPERIMENTAL COMBUSTION ANALYSIS OF A HSDI DIESEL ENGINE FUELLED WITH PALM OIL BIODIESEL-DIESEL FUEL BLENDS  [cached]
JOHN AGUDELO,ELKIN GUTIéRREZ,PEDRO BENJUMEA
DYNA , 2009,
Abstract: Differences in the chemical nature between petroleum diesel fuels and vegetable oils-based fuels lead to differences in their physical properties affecting the combustion process inside the engine. In this work a detailed combustion diagnosis was applied to a turbocharged automotive diesel engine operating with neat palm oil biodiesel (POB), No. 2 diesel fuel and their blends at 20 and 50% POB by volume (B20 and B50 respectively). To isolate the fuel effect, tests were executed at constant power output without carrying out any modification of the engine or its fuel injection system. As the POB content in the blend increased, there was a slight reduction in the fuel/air equivalence ratio from 0.39 (B0) to 0.37 (B100), an advance of injection timing and of start of combustion. Additionally, brake thermal efficiency, combustion duration, maximum mean temperature, temperature at exhaust valve opening and exhaust gas efficiency decreased; while the peak pressure, exergy destruction rate and specific fuel consumption increased. With diesel fuel and the blends B20 and B50 the same combustion stages were noticed. However, as a consequence of the differences pointed out, the thermal history of the process was affected. The diffusion combustion stage became larger with POB content. For B100 no premixed stage was observed.
COMBUSTION CHARACTERISTICS OF DIESEL ENGINE OPERATING ON JATROPHA OIL METHYL ESTER
Doddayaraganalu Amasegoda Dhananjaya,Chitrapady Visweswara Sudhir,Padmanbha Mohanan
Thermal Science , 2010, DOI: tsci1004965d
Abstract: Fuel crisis because of dramatic increase in vehicular population and environmental concerns have renewed interest of scientific community to look for alternative fuels of bio-origin such as vegetable oils. Vegetable oils can be produced from forests, vegetable oil crops, and oil bearing biomass materials. Non-edible vegetable oils such as jatropha oil, linseed oil, mahua oil, rice bran oil, karanji oil, etc., are potentially effective diesel substitute. Vegetable oils have reasonable energy content. Biodiesel can be used in its pure form or can be blended with diesel to form different blends. It can be used in diesel engines with very little or no engine modifications. This is because it has combustion characteristics similar to petroleum diesel. The current paper reports a study carried out to investigate the combustion, performance and emission characteristics of jatropha oil methyl ester and its blend B20 (80% petroleum diesel and 20% jatropha oil methyl ester) and diesel fuel on a single-cylinder, four-stroke, direct injections, water cooled diesel engine. This study gives the comparative measures of brake thermal efficiency, brake specific energy consumption, smoke opacity, HC, NOx, ignition delay, cylinder peak pressure, and peak heat release rates. The engine performance in terms of higher thermal efficiency and lower emissions of blend B20 fuel operation was observed and compared with jatropha oil methyl ester and petroleum diesel fuel for injection timing of 20° bTDC, 23° bTDC and 26° bTDC at injection opening pressure of 220 bar.
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