Ever increasing drift of energy consumption due to growth of population, transportation and luxurious lifestyle has motivated researchers to carry out research on biofuel as a sustainable alternative fuel for dieselengine. Biofuel such as biodiesel and ethanol, produced from renewable feedstocks, are the most appropriate alternative of petroleum fuels. However, direct using of ethanol in diesel fuel face some technical problem especially in cold weather, due to low cetane number, lower flash point and poor solubility. Biodiesel can be blended with both ethanol and diesel fuel and biodiesel–alcohol–dieselblends can be used in diesel engines. The aim of this review paper is to discuss the effect of mixed blends of biodiesel alcohol and diesel on engineperformance and emission parameters of a dieselengine. Most of the researchers reported that adding ethanol into biodiesel-diesel blend in diesel engines significantly reduce HC, PM, NOx and smoke emissions but slightly increase fuel consumption. The study concluded that biodiesel-diesel-ethanol blend can be used as a substitute of petro-diesel fuel to reduce dependency on fossil fuel as well as the exhaust emissions of the engine.
Biodiesel is an attractive alternative fuel for diesel engines.The feedstock for biodiesel production is usually vegetable oil, pure oil or waste cooking oil, or animal fats The most common way today to produce biodiesel is by transesterification of the oils with an alcohol in the presence of an alkaline catalyst. It is a low temperature and low‐ pressure reaction. It yields high conversion (96%-98%) with minimal side reactions and short reaction
The unburnt HC emissions for diesel, WCOME, and WCOME- GRAPHENE blended fuels are shown in Figure 4.6. The HC emission for WCOME operation is higher compared to neat diesel due to its lower thermal efficiency resulting in abnormal combustion . The HC emissions gradually decreases with the addition of GRAPHENE nanoparticles to WCOME due to catalytic activity and better combustion characteristics of GRAPHENE nanoparticles which leads to enhanced combustion. A GRAPHENE nanoparticle increases the catalytic activity and chemical activity which leads to complete combustion of fuel. WCOME+60ppm gives better performance as compared to WCOME+20ppm due to the increased dosing level of GRAPHENE nanoparticles. That provides higher surface area which leads to greater combustion characteristics . It was observe that 4.47% for (WCOME+20ppm), 7.69% for (WCOME+40ppm) and 9.30% for (WCOME+60ppm) reduction in HC emission as compared to neat WCOME.
extensively studied, but even today the question of which blend of methyl ester-diesel is best suitable for current dieselengine is yet remains unanswered. Comparing to laboratory testing and Actual testing where transport vehicles are studied on street, the only operating parameters studied are load and speed which define engine efficiency and fuel utilization for a particular length. In this paper, spotlight is focused to explain experimentally the performance and exhaust emission characteristics of a Direct Injection –Compression Ignition engine when fuelled with Palm oil methyl ester biodiesel (PB10,P B20,PB30) addition of ethanol (E5% and E10%) over the various loading conditions on the engine. The observations made are lesser Carbon Monoxide emissions and Exhaust Gas temperatures reduced within increase of doping of ethanol content in Blends of Methyl Ester and its blends .
counterparts. Satyanarayana and Muraleedharan  studied the rubber seed oil biodiesel in a single cylinder dieselengine at difference loads and a constant speed of 1500 rpm. They reported less torque and power, 4.95% lower BTE, higher BSFC, 0.037% lower CO, lower THC and higher NOx compared to diesel fuel. Raheman et al.  investigated the performance and emissions of the Mahua-simarouba oil mixture biodiesel using a single cylinder dieselengine. The results showed higher BSFC and NOx while BTE, CO and THC were lower compared to diesel fuel. Michael et al.  investigated the soybean-soapstock biodiesel in a dieselengine and observed a reduction in CO and THC. Due to the slightly chemical composition differences, biodiesel fuel combustion may differ from the actual diesel fuel and results in different emissions and performance. Investigations of different oils blended biodiesels in a dieselengine in the literature, mostly focused on examining one parameter effect such as the engine speed, engine load, blends ratio, IT (injection timing) or IP (injection pressure) at a time as presented in Supplementary 1. However, the dieselenginecombustion process is influenced by the combined effects of all the above mentioned parameters. Therefore, a multi-variation investigation could provide clear knowledge on the combustion behaviour rather than one variable at a time. Multi- variation studies, methods such as DoE (Design of experiments), ANN (artificial neural network) and fuzzy logic are suitable to explore the combination effects of input parameters. DoE is accepted the most effective and economical technique compared to ANN and fuzzy logic. Bhattacharya et al.  investigated the effects of load, speed and injection timing on the BSFC, exhaust emissions and noise. BSFC limitation is reported by lower load, noise
Performance and exhaust emissions of a dieselengine run on blends of biodiesel Jatropha with diesel fuel. Engineperformance was improved and harmful exhaust emissions were reduced. Combustion characteristics of biodiesel are near to diesel fuel. Biodieselblends reduced smoke opacity, particulate matters, unburned hydrocarbons, carbon dioxide and carbon monoxide emissions but nitrogen oxide emissions were increased. An experimental investigation was run to evaluate the performance and exhaust emissions of a single cylinder, air cooled, four stroke, direct injection dieselengine fueled with biodiesel Jatropha and its blends (B20, B40, B60, B80 and B100) with diesel fuel. Lower blend of biodiesel (B20) is a best alternative fuel at full load condition . Generally, waste cooking oil biodiesel led to a reduction of HC and CO emissions but an increase in NOx emission . Performance and emissions of a dieselenginefuelled with castor biodieselblends and pure diesel fuel separately was experimentally investigated at various engine loads. B15 and B20 biodieselblends at full load gave the best brake specific fuel consumptions (BSFC) of dieselengine. At these conditions, increase of NOx is about 4% compared to diesel fuel . Biodiesel caused reductions in engine torque and power, but the lower emissions in carbon dioxide, carbon monoxide was produced as compared to diesel fuel with an increase in NOx emissions compared to diesel fuel .
Sayin  studied the effects of methanol-diesel (M5 and M10) and ethanol-diesel (E5 and E10) fuel blends in a single cylinder, four-stroke, direct injection (DI) dieselengine. The results showed that the brake thermal efficiency (BTE), CO, HC and smoke emissions decreased, while brake specific fuel consumption (BSFC) and NOx emissions increased with methanol-diesel and ethanol-diesel fuel blends. Guido et al.  investigated the effect of bioethanol with rapeseed methyl ester and dieselblends in a four- cylinder light duty dieselengine with closed loop combustion control. The results showed a strong smoke and NOx emissions reduction, while higher BSFC, CO and HC emissions were observed with bioethanol blends. Zhu et al.  studied the effects of ethanolblends in four-cylinder direct injection (DI) dieselengine. The results indicated that ethanol-biodieselblends showed higher brake thermal efficiency (BTE) and lower NOx and PM emissions compared to diesel fuel. Increasing the ethanol amount in the fuel blends resulted in higher brake BSFC, HC and CO emissions.
In the present days, use of fuel is picked its way of increase and price is also going to increase undoubtedly. So the use of present sources of petroleum becomes a serious issue. To provide the diesel fuel for diesel engines approximately not more than 40 years. Limited energy sources leads to the warning of potential lack of energy in the future. Approximately 1/3 of the petroleum fuels are consumed in the IC engines and exhaust gases emitted from these engines are one of the main reasons for the environmental pollution. In the last years, many studies on the IC engines aiming to reduce exhaust emissions have been carried out by changing operating parameters such as valve timing, injection timing, and atomization rate. At the same time, depletion of fossil fuels and environmental considerations has led to investigations on the renewable fuels such as ethanol, hydrogen, and biodiesel. Biodiesel derived from biological sources, among them lipid materials such as fats and oils have received increasing attention. The increasing demand of petroleum in developing countries like China, Russia and India has increased oil prices. Besides, the combustion of petroleum based fuels causes environmental problems, which threaten wild and human life, impacts on the environment and human health. In addition, the combustion products causes global warming one of the most important today’s world problem. The global warming is caused of emissions like carbon monoxide (CO), carbon dioxide (CO2), sulphur dioxide (SO2) and nitrogen oxides (NOx). In power system of using petroleum fuels, these components are emitted through the combustion process. Concerning environmental damage the transport sector has a clear responsibility. Its part in global warming potential has increased from year by year and now bigger than those of the domestic and industrial sector, while it highly constitutes the total emissions of this pollution type.
Ethanol was known as possible candidate for alternative fuel and many studies are conducted to develop this fuel . Ethanol has a number of advantages compared to fossil fuels that can be directly mixed in the fuel tank, is injected into the combustion chamber and burned in order to reduce exhaust emissions . This material is derived from a renewable resource that is not limited in the form of plants that can grow well or biomass containing sugar, starch or cellulose . By mixing the ethanol with fossil based fuels in dieselengine may help extend the life of the supply of fuel, ensure the safety of the larger fuel supply, reduce environmental problem, increase agricultural economy and avoid dependence on fossil fuel-producing countries. Based on previous studies, it is very difficult to get a mixture stability of ethanoldiesel fuel by direct mixing [7,8]. Today, the problem can be solved by adding octyl nitrate , nitrite glycol , triethilene glycol dinitrate (TEGDN) , and methyl ester [7,9] as an additives.
Abstract. Bio fuels based on vegetable oils offer the advantage being a sustainable, annually renewable source of automobile fuel. Despite years of improvement attempts, the key issue in using vegetable oil-based fuels is oxidation stability, stoichiometric point, bio-fuel composition, antioxidants on the degradation and much oxygen with comparing to diesel gas oil. Thus, the improvement of emissions exhausted from diesel engines fueled by biodiesel derived from palm oil is urgently required to meet the future stringent emission regulations. Purpose of this study is to explore how significant the effects of palm oil blending ratio on combustion process that strongly affects the vehicles performance and exhaust emissions. The engine speed was varied from 1500 ∼ 3000 rpm, load test condition varied by Dynapack chassis dynamometer from 0 ∼ 50% and palm oil blending ratio from 5 ∼ 15vol% (B5 ∼ B15). Increased blends of biodiesel ratio is found to enhance the combustion process, resulting in decreased the HC emissions with nearly equal of engineperformance. The improvement of combustion process is expected to be strongly influenced by oxygenated fuel in biodiesel content.
Valentino, G., Corcione, F. E., Iannuzzi, S. E., and Serra, S. 2012. Experimental study on performance and emissions of a high speed dieselenginefuelled with n-butanol dieselblends under premixed low temperature combustion. Fuel. 92(1): 295-307. Xin, J., Imahara, H., and Saka, S. 2008. Oxidation stability of biodiesel fuel as prepared
consumption (BSFC). Drastic reduction in smoke is observed with ethanol at higher engine loads. Nitrogen oxide (NOx) emissions and hydrocarbon (HC) emissions are slightly higher for blended fuel with ethanol, but carbon monoxide (CO) is slightly lower. However, the blended fuels with ethanol could lead to reduce both of NOx and HC emissions of a dieselengine , where biodiesel was blended with 5%, 10% and 15% by volume of ethanol and tested in a 4-cylinder direct- injection dieselengine. This paper prepared by J. Wang, J. Xiao and S. Shuai,  explores the possibility to significantly reduce the particulate matter (PM) emissions by new fuel design. Several oxygenated blends were obtained by mixing the biodiesel, ethanol, and dimethyl carbonate (DMC), and diesel fuels. The tests were conducted on two heavy-duty diesel engines, both with a high-pressure injection system and a turbocharger. The total PM and its dry soot (DS) and soluble organic fraction (SOF) constituents were analyzed corresponding to their specific fuel physiochemical properties. A blended fuel that contains biodiesel, DMC, and high cetane number diesel fuels was chosen eventually to enable the diesel engines to meet the Euro IV emission regulation. Based on the test results, the basic design principles were derived for the oxygenated blends that not only need the high oxygen content, but also the high cetane number and the low sulfur and low aromatic contents. The fuels used in this study include a baseline diesel fuel, three types of biodiesels, and their blends with ethanol, DMC, DMM, and straight-run (or directly distilled) diesel fuel. Ethanol, DMC, and DMM are used as oxygenates to raise the oxygen content, while the straight-run diesel fuel is used to improve the auto-ignition capability of the blended fuel. When fueling oxygenated blends, the direct soot constituent in PM emissions decreases significantly as the fuel oxygen
As we need an alternating fuel that will replace diesel fuel in order to reduce the harmful emissions coming out of engine as exhaust by products, which necessitates the improvement in engineperformance and increase in combustion characteristics of fuels in the combustion chamber. As biodiesels are having high viscosity and higher flashpoint than diesel, it will be difficult to use biodiesel as a fuel alone in present diesel engines. Hence it is preferred to blend biodiesel with diesel to get required properties of blend that will suit the present diesel engines. But higher kinematic viscosity of biodiesel/dieselblends as compared to diesel affects the atomization of fuel in the combustion chamber which further reduces the combustion pressure and temperature and reduces the power output of the engine. This necessitates the addition of ethanol as an additive in the blends which further enhances the hot flow, cold flow and thermo-physical properties of the biodiesel/dieselblends. Therefore in this study feedstock of palm oil biodiesel is used as fuel with 5% ethanol by volume as an additive in the blends of palm oil biodiesel/dieselblends. Hot flow and cold flow properties of blends of palm oil biodiesel/ethanol/dieselblends are experimentally investigated as per IS 1448 standards. Investigation outcome shows that ethanol as an additive improves the kinematic viscosity of blends of palm oil biodiesel/diesel by 4% lesser than biodiesel/diesel blend without ethanol and 12% higher than diesel. But on the other hand calorific value of the blends with the addition of ethanol decreases calorific value by 6.27% than biodiesel/diesel blend without ethanol and 6.87 % than diesel. Most importantly the cold flow properties are enhanced by the addition of ethanol in the blend such as cloud point increases by 13 % than biodiesel/diesel blend without ethanol and pour point increases by 14% than biodiesel/diesel blend without ethanol. The combustion and performance analysis are improved with the addition of ethanol and decreases the harmful emissions from the exhaust manifold of the engine. The effect of ethanol as an additive in the blends of palm oil biodiesel/diesel blend on properties, performance, and combustion and on emissions are studied in this paper.
D.C. Rokopoulos observed that blends congaing ethanol shows high HC emission  the reason is unburned ethanol exhausted from combustion chamber. Emission is total unburned hydrocarbons (HC) emitted by the ethanolblends are higher than those of the corresponding 100 % diesel fuel. High HC emission means that there is some unburned ethanol emitted in the exhaust due to the larger ethanol dispersion region in the combustion chamber. Methyl soyate has a higher cetane number than diesel, which will result in more complete combustion in the cylinder. Thus, B20 had less THC emissions than diesel fuel .
were mainly due to the catalytic activity of nanoparticle. Mean while, Selvan et al.  added cerium oxide nanoparticle of 25 ppm in diesel-biodiesel-ethanolblends and found improved brake specific fuel consumption with reduction of Unburned HC, CO, NO and Smoke opacity. Basha and Anand  blended Carbon Nanotube at 25, 50 and 100 ppm in Jatropha methyl ester emul- sion (5% of water and 2% of surfactants (by volume)) and found drastic percentage reduction of NO by 29 % and smoke opacity by 28 % in a single cylinder, four-stroke, direct injection dieselengine. The same team  carried out experimental investiga- tion with alumina nanoparticle, blended at 25 and 50 ppm in bio- diesel emulsion fuel and observed drastic percentage reduction of NO by 27 %, smoke opacity by 40 % with marginal reduction of HC and CO emission. Tewari et al.,  conducted experimen- tal investigation in a single cylinder four stroke direct injection dieselengine with CNT blended at 25 and 50 ppm in honge oil methyl ester and determined substantial percentage reduction of NO by 25 %. Bhagwat et al.,  established 7.6 % improvement in brake thermal efficiency for 50 ppm addition of graphene to Honge Oil Methyl Ester when compared with neat Honge Oil Methyl Ester. From the nanoparticle study, it is observed that in order to improve both the performance and emission character- istics of engine evenly, nanoparticle will be the most promising additive than the antioxidant.
Abstract :The depletion of world petroleum reserves and increased environmental concern has stimulated the search of alternative fuel which is to be environment friendly. Bio-fuels have the potential to become alternative fuel for fossil fuels. Biodiesel is renewable, reliable, biodegradable and regarded as a clean alternative fuel to reduce exhaust emissions. In recent years, much research has been carried to find suitable alternative fuel to petroleum products. In the present investigation experimental work has been carried out to analyze the performance and emissions characteristics of a single cylinder compression ignition DI enginefuelled with the blends of mineral diesel and biodiesel. The simarouba biodiesel is considered as alternative fuel to diesel. A large amount of tree borne oils and fats are available for biodiesel production in developing and under develop countries. Simarouba glauca oil is one of these oils.
to determine the optimal biodiesel ratio by conducting numerous experiments on a dynamometer subject to the user’s requirements. Therefore, creating a computational model for biodiesel engines may be the best solution to the above abridgement because the optimal biodiesel ratio can then be determined by applying computer-aided optimization method to the engine model. However, the main aim of this study is to develop a combustion model to maximize the combustionperformance of an automobile enginefuelled with second generation biodiesel produced from BLS. The computational fluid dynamics (CFD) model for the turbulent combustion of biodiesel in an internalcombustionengine will allow a range of benefits to be evaluated and be a guide for engine manufacturers, biodiesel producers, biodiesel users and policy makers. Some of these benefits include improving internalcombustionengine technology, reducing harmful gas emissions, and increasing fuel efficiency, sustainability and optimum uses of second generation biodiesel as engine fuel. Biodiesel from vegetable oils is one of the renewable fuels that can be used in a dieselengine with or without some minor modifications. Using Biodiesel increases the oxygen content resulting in better combustion. Other properties of biodiesel are also similar to diesel. However, higher viscosity and density of the biodiesel lead to higher BSFC and higher smoke emissions. To minimize this limitation, one alternate method is addition of ethanol. The addition reduces the viscosity and density of the blend and becomes similar to diesel. Biodiesel-diesel- ethanolblends produce lesser emissions of smoke and NOx emissions compared to diesel, due to addition of ethanol. More and more consumption of fossil fuels evacuate the oil reserves at a rapid rate. The projections of 30 year period of 1990–2020 from a survey resulted that the demand
Typical curves of average in-cylinder pressure and heat release rate for different ethanol concentrations are shown in Fig. 2, for engine load of 20 kW. At this load, the peak pressure was higher for B7E5 (3367 kPa), followed by B7E15 (3358 kPa), B7E10 (3350 kPa) and B7E0 (3327 kPa). For higher loads the highest peaks of pressure and heat release rates were found as the ethanol content in the fuel was increased. The air/fuel mixture formed by the fuel blends with ethanol during the premixed phase was responsible to increase the peak pressure relative to B7E0 . As the engine load increases the peak cylinder pressure is increased and occurs away from the top dead center (TDC). The net heat release rate is comprised of a premixed combustion phase, followed by a diffusive combustion phase. The maximum heat release rate shows a growth up to medium loads, but decreases with approximation of the maximum loads. For all other load conditions the trend of in-cylinder pressure curves and net heat release are similar. Zhu et al.  reported the same behavior.
esterified (biodiesel) forms. Their use in form of methyl esters in non-modified engines has given encouraging results. Use of edible oil to produce biodiesel in India is also not feasible in view of big gap in demand and supply of such oils. Under Indian condition only such plants can be considered for biodiesel, which produce non-edible oil in appreciable quantity and can be grown on large scale on non-cropped marginal lands and waste lands. Out of many available non-edible vegetable crops, Jatropha curcas is the most widely used biodiesel crops. Several studies have been conducted using biodiesel produced from Jatropha curcas (Senthil et al. 2003; Reddy et al. 2006).
This paper evaluates and quantifies the environmental impact from the use of some renewable fuels and Fossils fuels in internalcombustion engines. The following fuels are evaluated: gasoline blended with anhydrous ethyl alcohol (anhydrous ethanol), conventional diesel fuel, biodiesel in pure form and Blended with diesel fuel, and natural gas. For the case of biodiesel, its complete life cycle and the closed Carbon cycle (photosynthesis) were considered. This study reports the effects of engine load and biodiesel percentage on the performance of a dieselenginefuelled with diesel-biodieselblends by experiments and a new theoretical model based on the finite-time thermodynamics (FTT). In recent years, biodiesel utilization in diesel engines has been popular due to depletion of petroleum-based diesel fuel. In this study, performance of a single cylinder, four-stroke, direct injection (DI) dieselenginefuelled with diesel-biodiesel mixtures has been experimentally and theoretically investigated. The ecological efficiency concept depends on the environmental impact caused by CO2, SO2, NOx and particulate material (PM) emissions. The resultant pollution of each one of the mentioned fuels are analysed, considering separately CO2, SO2, NOx and particulate material(PM) emissions. The ecological efficiency for pure biodiesel (B100) is 86.75%; for biodiesel blended with conventional diesel fuel (B20, 20% biodiesel and 80% diesel), it is 78.79%. Finally, the ecological efficiency for conventional diesel, when used in engines, is 77.34%; for gasoline, it is 82.52%, and for natural gas, it is 91.95%. All these figures considered a thermal efficiency of 30% for the internalcombustionengine.