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1.
The world is faced with a problem of air pollution due to the exhaust emissions from automobile. Recently, lots of researchers have been attracted to develope various alternative fuels and to use renewable fuels as a solution of these problems. There are many alternative fuels studied in place of diesel fuel made from petroleum. Biodiesel fuel (BDF) is a domestically produced, renewable fuel that can be manufactured from vegetable oils, used vegetable oils, or animal fats. In this study, the usability of BDF, one of the oxygenated fuels as an alternative fuel for diesel engines was investigated in an IDI diesel engine. Emissions were characterized with a neat BDF and with a blend of BDF and conventional diesel fuel. Since the BDF includes oxygen of about 11%, it could influence the combustion process strongly. Therefore, the use of BDF resulted in lower emissions of carbon monoxide and smoke emissions with some increase in emissions of oxides of nitrogen. It is concluded that BDF can be utilized effectively as a renewable fuel for IDI diesel engines.  相似文献   

2.

Biodiesel is an environmentally friendly fuel that can replace diesel in compression ignition engines without changing the engine structure. Biodiesel is typically manufactured from vegetable oils and animal fats, which give the fuel its oxidation stability and cold-flow properties, respectively. However, the kinematic viscosity of biodiesel can cause engine performance problems such as incomplete combustion and sludge formation due to insufficient fuel atomization. To address these problems, in this study, a pretreatment technology that lowers the kinematic viscosity of biodiesel made from blended animal fat and vegetable oil was developed. The results of application of the pretreated fuel to a single-cylinder power tiller engine indicated that it produced 88.3–99.8 % of the brake power produced by conventional diesel. In addition, although the pretreated biodiesel exhaust included increased amounts of nitrogen oxides and carbon dioxide emissions, the proposed fuel also decreased the amounts of hydrocarbon and carbon monoxide emissions compared with conventional diesel emissions.

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3.
Diesel engines have proven their utility in the transportation, agriculture, and power sectors in India. They are also potential sources of decentralized energy generation for rural electrification. Concerns on the long-term availability of petroleum diesel and the stringent environmental norms have mandated the search for a renewable alternative to diesel fuel to address these problems. Vegetable oils have been considered good alternatives to diesel in the past couple of years. However, there are many issues related to the use of vegetable oils in diesel engine. Jatropha curcas has been promoted in India as a sustainable substitute to diesel fuel. This study aims to develop a dual fuel engine test rig for evaluating the potential suitability of Jatropha oil as diesel fuel and for determining the performance and emission characteristics of an engine with Jatropha oil. The experimental results suggest that engine performance using Jatropha oil is slightly inferior to that of diesel fuel. The thermal efficiency of the engine was lower, while the brake-specific fuel consumption was higher with Jatropha oil compared with diesel fuel. The levels of nitrogen oxides (NOx) from Jatropha oil during the entire duration of the experiment were lower than those of diesel fuel. The reduction of NOx was found to be an important characteristic of Jatropha oil as NOx emission is the most harmful gaseous emission from engines; as such, its reduction is always the goal of engine researchers and makers. During the entire experiment, carbon monoxide (CO), hydrocarbon (HC), and carbon dioxide (CO2) emissions in the case of using Jatropha oil were higher than when diesel fuel was used. The higher density and viscosity of Jatropha oil causes lower thermal efficiency and higher brakespecific fuel consumption. The performance and emission characteristics found in this study are significant for the study of replacing diesel fuel from fossils with Jatropha oil in rural India, where the availability of diesel has always been a problem.  相似文献   

4.
Owing to the increasing cost of petroleum products, fast depletion of fossil fuel, environmental consideration and stringent emission norms, it is necessary to search for alternative fuels for diesel engines. The alternative fuel can be produced from materials available within the country. Though the vegetable oils can be fuelled for diesel engines, their high viscosities and low volatilities have led to the investigation of its various derivatives such as monoesters, known as bio diesel. It is derived from triglycerides (vegetable oil and animal fates) by transesterification process. It is biodegradable and renewable in nature. Biodiesel can be used more efficiently in semi adiabatic engines (Semi LHR), in which the temperature of the combustion chamber is increased by thermal barrier coating on the piston crown. In this study, the piston crown was coated with ceramic material (TiO2) of about 0.5 mm, by plasma spray method. In this present work, the experiments were carried out with of Pongamia oil methyl (PME) ester and diesel blends (B20 & B100) in a four stroke direct injection diesel engine with and without coated piston at different load conditions. The results revealed 100% bio diesel, an improvement in brake thermal efficiency (BTE) and the brake specific fuel consumption decreased by about 10 % at full load. The exhaust emissions like carbon monoxide (CO) and hydrocarbon (HC) were decreased and the nitrogen oxide (NO) emission increased by 15% with coated engine compared with the uncoated engine with diesel fuel. The peak pressure and heat release rate were increased for the coated engine compared with the standard engine.  相似文献   

5.
Biodiesel fuels that consist of saturated and unsaturated long-chain fatty acid alkyl esters are an alternative diesel fuel produced from vegetable oils or animal fats. However, autoxidation of biodiesel fuels during storage is easily caused by air, reducing fuel quality by adversely affecting its properties such as kinematic viscosity and acid value. One approach to improve the resistance of biodiesel fuels to autoxidation is to mix them with antioxidants. This study investigated the effectiveness of five such antioxidants in mixtures with biodiesel fuels produced by three biodiesel manufacturers: butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), tert-butylhydroquinone (TBHQ), propyl gallate (PrG) and α-tocopherol. An engine test was also performed to investigate the combustion characteristics of biodiesel fuel with antioxidants in an indirect-injection (IDI) diesel engine. Oxidation stability was determined using Rancimat equipment. The results showed that TBHQ, BHA, and BHT were the most effective and α-tocopherol was the least effective in increasing the oxidation stability of biodiesel. The combustion characteristics and exhaust emissions in diesel engine were not influenced by the addition of antioxidants in biodiesel fuel. This study recommends TBHQ and PrG to be used for safeguarding biodiesel fuel from the effects of autoxidation during storage.  相似文献   

6.
In this study, experiments on the simultaneous reduction of smoke and NOx emissions of indirect-injection (IDI) diesel engines were conducted using a biodiesel fuel (BDF) and ethylene glycol mono-n-butyl ether (EGBE), which is an oxygenated fuel of mono-ethers, as a pre-processing method and by applying cooled EGR. A four-cylinder, water-cooled IDI diesel engine was used, while the engine performance and emission characteristics were considered using diesel fuel, BDF 100%, and a mixed fuel BDF and EGBE (maximum EGBE mixing ratio in mixed fuel: 20 vol-%). Results showed the BDF and the BDF and EGBE mix had significantly better smoke reduction effects than the diesel fuel. In particular, the use of the BDF and EGBE mix and the simultaneous application of 10% cooled EGR were confirmed to have reduced both smoke and NOx emissions.  相似文献   

7.
Due to the shortage of petroleum products and its increasing cost, efforts are on to develop alternate fuels, especially diesel oil, for partial or full replacement. Also, internal combustion engines generate undesirable emissions during combustion process. The emissions exhausted in to the surroundings pollute the atmosphere and causes several problems. The emissions of concern are: unburnt hydrocarbons, oxides of carbon, and oxides of nitrogen (NOX). Advanced diesel fuel formulations offer significant emission reductions to new and older in-use engines every time the fuel tank is filled. The addition of water to diesel fuel lowers particulate emissions by serving as diluents to the key combustion intermediates that lead to particulate formation. The incorporation of water also reduces NOX emissions by lowering the peak combustion temperatures through high heat of vaporization. When using water blend diesel, the engine fuel system recognizes the liquid as diesel fuel because the water droplet is encapsulated within a diesel fuel. In this experiment, we have used single cylinder four-stroke engine and the water-blend diesel emulsion is used and the diesel emission test, emulsion emission test, and various gases has been analyzed; smoke meter test is also conducted for various rate of loads. The test results from the engine fuelled with water-blend diesel showed reduction in emissions as compared to that of engine fuelled with conventional diesel. The better emissions in the CI engine using water-blend diesel is due to the incorporation of water which reduces NOX emissions by lowering the peak combustion temperatures. Water-blend fuel enhances fuel atomization by micro-explosion. The addition of water to diesel fuel lowers particulate emissions by serving as diluents to the key combustion intermediates that lead to particulate formation  相似文献   

8.
I. Celik  O. Aydin 《摩擦学汇刊》2013,56(3):424-431
In this study, the effects of biodiesel use in a diesel engine on an injector and fuel injection pump piston were experimentally analyzed. To this end, two engines with the same technical specifications were used; petroleum diesel was used in one of the engines and 100% (B100) biodiesel was used in the other engine. After the engines were run for 200 h, their injectors and pump pistons were examined and compared by performing scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) analysis measurements. SEM and EDX analyses showed significant structural changes on the surfaces of the injector nozzle and pump piston in the event that B100 is used.  相似文献   

9.

The use of biodiesel-blended fuels in diesel engines improves the engine performance parameters and the partial recovery of incomplete combustion products, while also increasing the level of NOx emissions. In this study; biodiesel obtained through the transesterification of waste chicken frying oil was mixed with diesel fuel (90% diesel + 10% biodiesel-B10), and was then used as fuel in a direct injection diesel engine. To reduce the increased NOx emissions caused by the use of B10 fuel, the steam injection method (which is one of the NOx reduction methods) was applied. Steam was injected into the intake manifold at different ratios (5%-S5, 10%-S10 and 15%-S15) and at the time of the induction stroke with the aid of an electronically controlled system. Based on the study results, it was observed that steam injection into the engine using B10 fuel improved both the engine performance and the exhaust emission parameters. It was determined that the S15 steam injection ratio resulted in the best engine performance and emissions parameters. In comparison to STD fuel; the highest increase observed at the S15 steam injection ratio in the effective engine power was 2.2%, while the highest decrease in the specific fuel consumption was 3.4%, the highest increase in the effective efficiency was 3.5%, and the highest decrease in NOx emissions was 13.7%.

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10.
Effects of refined palm oil (RPO) fuel on wear of diesel engine components   总被引:2,自引:0,他引:2  
Surapol Raadnui  Anant Meenak 《Wear》2003,254(12):1281-1288
In this particular research work, the effects of refined palm oil (RPO), as alternative fuel, on wear of diesel engine components are assessed. Fleet testing is carried for the qualifying candidates diesel fuel replacement, i.e. 100% RPO fuel or 50% RPO and 50% conventional diesel fuel mixture. The base line of the fleet testing is using pure conventional petroleum diesel fuel as an energy source in one of the tested vehicles in the fleet. Analysis of used engine lubrication oil, taken when the oil was changed on the vehicles, was compared to the analysis of used oil samples pulled from 100% diesel fuel engines. The finding suggested that the pure RPO and RPO blended fueled engines were wearing at a normal rate.  相似文献   

11.
Biodiesel has become an increasingly significant alternative fuel to replace conventional diesel completely or partially. Although biodiesel has several advantages, such as environmental friendliness, renewability, and reduced emissions, it also has major drawbacks. Tribology is one of the major concerns for biodiesel usage, in which biodiesel lubricity deteriorates by usage and/or by storage because of its oxidative nature. The present study aims to investigate the lubrication behavior of oxidized and pure palm biodiesel blends by using a four-ball tribotester machine. Tests were carried out in diesel, pure biodiesel (B100), their blends (B10 [10% biodiesel in diesel], B20, B30, and B50), and oxidized biodiesel (Oxd B100) and its blends (Oxd B10, Oxd B20, Oxd B30, and Oxd B50). Tests were conducted at room temperature under a normal load of 40 kg for 1 h at 1,200 rpm. Surface analyses were carried out by scanning electron microscopy, energy-dispersive spectrometry, and optical microscopy, and fuel analysis was performed by gas chromatography–mass spectroscopy. Diesel fuel showed the highest wear and friction. Surface deformation, wear, and friction decreased as the biodiesel concentration increased in the blend. Oxidized biodiesel blends showed improved lubricity compared to pure biodiesel and blends. However, Oxd B100 showed higher wear than Oxd B50.  相似文献   

12.
Low-sulfur and low-aromatic diesel fuels are being introduced in order to reduce various types of emissions in diesel engines to levels in compliance with current and impending U.S. federal regulations. The low lubricity of these fuels, however, poses major reliability and durability problem for fuel injection components that depend on diesel fuel for their lubrication. In the present study, the authors evaluated the scuff resistance of surfaces in regular diesel fuel containing 500 ppm sulfur and in Fischer-Tropsch synthetic diesel fuel containing no sulfur or aromatics. Tests were conducted with the high frequency reciprocating test rig (HFRR) using 52100 steel balls and H-13 tool-steel flats with and without Argonne's special carbon coatings. Test results showed that the sulfur-containing fuels have about 20% higher scuffing resistance than does fuel without sulfur. The presence of the carbon coating on the flat increased scuffing resistance in both regular and synthetic fuels by about ten times, as measured by the contact severity index at scuffing. Coating removal was observed to be a necessary, but not sufficient condition for scuffing failure in tests conducted with coated surfaces. The loss of coating from the surface occurred by the two distinct mechanisms of spalling and wear.  相似文献   

13.
发动机燃用生物柴油的颗粒可溶有机组分及多环芳烃排放   总被引:5,自引:1,他引:5  
以一台车用柴油机为样机,研究发动机燃用生物柴油的常规排放,重点探讨其颗粒(Particulate matter,PM)、可溶有机组分(Soluble organic fraction,SOF)及多环芳烃(Polycyclic aromatic hydrocarbons,PAHs)的排放特性。所用燃油分别为柴油、生物柴油掺混配比为10%的B10燃油。结果表明,与柴油相比,该车用柴油机燃用B10燃油后颗粒、SOF和PAHs的质量排放均有所降低;NOx排放略有增加,HC和CO排放有所下降。B10燃油燃烧的颗粒SOF中醇类、酮类、醚类质量分数下降;脂类、酸类、醛类质量分数上升。在检测到的12种PAHs中,B10燃油有10种质量排放减少,尤其是苯并(a)芘等高环数致癌性的PAHs降幅明显,这表明发动机燃用生物柴油后,排气颗粒的化学成分毒性有所降低。  相似文献   

14.
The use of renewable, bio-based fuels has become increasingly widespread in recent years, with a major example being biodiesel, a bio-derived alternative to Number 2 diesel fuel. The increased usage of biodiesel gives rise to an augmented need to understand its tribological effects on critical engine components. This study focused on determining the tribological performance of soybean-based B100 (i.e., pure) biodiesel within a fuel injector with varying oscillating frequency by performing a series of linear reciprocating tribological tests of biodiesel-lubricated interfaces with varying reciprocating frequency. Comparison of friction coefficient variation with reciprocating frequency indicated a transition from boundary lubrication to hydrodynamic lubrication as the frequency increased, while hysteresis loop and energy loss observations showed a transition between full stick and partial slip contact with increasing frequency. However, observations of induced wear showed the wear to increase with increasing frequency, most likely due to the augmented number of sliding cycles as well as an increased degree of interfacial slip.  相似文献   

15.
A number of studies have recently been conducted to determine a suitable alternative fuel for conventional engine. The use of renewable fuels such as bio-ethanol, biogas, and biodiesel is thus investigated for this purpose. Performance tests were conducted on an indirect injection compression ignition engine by using diesel, unheated jatropha oil (JO), and preheated JO as fuels. The effects of fuel injection pressure and fuel inlet temperature on engine performance and emission for the different fuels were analyzed. Test results showed that the brake thermal efficiency of the engine with heated JO oil is superior to that with unheated JO, increasing from 28.4% with neat unheated JO to a maximum of 30.8%. The brake specific fuel consumption was reduced from 0.301 kg/kWh to 0.266 kg/kWh. Smoke opacity was also reduced relative to the neat unheated JO operation.  相似文献   

16.

Biodiesel is a renewable, easily biodegradable, eco-friendly and sustainable alternative energy source. In this investigation, crude oil was extracted from Spirulina maxima microalgae through biochemical conversion method with the help of soxhlet apparatus. Biodiesel production process parameters were optimized through base transesterification. Maximum biodiesel yield achieved was 87.75 % at optimal reaction condition after transesterification, when methanol to oil ratio was 6:1, catalyst loading was 1 % KOH (wt.%), temperature was 65 °C, and stirring speed was 600 rpm for a reaction time of 70 minutes. All the physicochemical properties of the produced biodiesel were determined and compared with the ASTM D6751 specification. Finally, performance and emission of an unmodified diesel engine was evaluated with 20 % and 40 % (v/v) biodiesel blends and compared the results with ordinary Diesel fuel (DF). Using biodiesel blends improves Hydrocarbon (HC) emission by 10-15 % and Carbon monoxide (CO) emission by 9.3-13.9 %. However, Brake specific fuel consumption (BSFC), Oxides of nitrogen (NOX), Carbon dioxide (CO2) and smoke opacity were found to be slightly higher for biodiesel blends, and Brake thermal efficiency (BTE) was found slightly lower than DF. Thus, Spirulina maxima serves as a potential feedstock for biodiesel production and prospective fuel in diesel engine application.

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17.

One of the most important basic requirements of diesel-powered vehicles that they have lower pollutant emissions and fuel consumption. In diesel engines, combustion and engine performance are influenced by the physical and chemical properties of the used fuel. Engine design studies are not enough to increase engine performance and reduce exhaust emissions alone. By adding fuel additives in diesel fuel, the physical and chemical properties of the fuel can be improved. Fuel additives affect engine performance, combustion and emissions positively by exerting catalyst effect during combustion. In this study, n-hexane and n-hexadecane were added in diesel fuel (D0) by volume of 4, 12 % and 20 %. With respect to D0 fuel, in DHD20 and DHX20 fuels engine torque increased by 1.60 % and 1.32 %, respectively, while the brake specific fuel consumption decreased by 3.12 % and 1.98 %, respectively. Maximum cylinder pressures and heat release rate values of the ingredient added fuels increased. It was seen that NOx emissions increased while HC, CO and soot emissions decreased with increasing contribution ratio.

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18.
In recent years, environmental awareness and legislation have focused public attention on vehicle emissions. Consequently, more research has been devoted to emissions and pollution by lubricants. A number of studies has been carried out to understand lubricant-related emissions and leak rates as well as the effects on fuel economy of using low viscosity grades of lubricant. The purpose of the present investigation was to develop for use in gasoline and diesel engines a crankcase lubricant which contained improved performance in engine cleanliness with fuel economy and a low rate of particle emissions. Emphasis was placed on low toxicology and rapid biodegradability because of the risk of unintentional emissions. Such a sophisticated lubricant is desirable not only for normal road vehicles but also and especially for use in ecologically sensitive areas. During the development of this lubricant, numerous laboratory tests were performed. In order to assess the quality and the fuel economy of the new lubricant, tests were carried out on an engine test rig and on a vehicle test bench. Field tests were run with various vehicles and stationary engines, using different fuel types. Unleaded gasoline, diesel fuels with a varying sulphur content, and rape seed oil methyl ester (RME) were used. This paper summarises the results of this investigation.  相似文献   

19.
The combustion and heat release of engines using diesel fuel and bio-diesel fuel have been investigated. The results illustrate that the combustion happens in advance and the ignition delay period is shortened. The initial heat release peak declines a little, the corresponding crankshaft angle changes in advance, and the combustion duration is prolonged. The economic performance and emission features of diesel engines using diesel fuel and bio-diesel fuel are compared. The results also show that the specific fuel consumption of bio-diesel increases by about 12% .The emissions, such as CO, HC, and particulate matter decrease remarkably whereas NOx increases a little.  相似文献   

20.
Particle size distribution and particle number concentration from diesel engines are subjects of significant environmental concerns especially in the EU. A few years ago, the UN-ECE PMP proposed a method for measuring particle emissions in the diluted exhaust of internal combustion engine vehicles, which has become a key method used in new dilution systems and sampling condition. This paper describes the effects of parameters such as condensation particle counter (CPC) according to test procedures, test fuel and vehicle test mode, including NEDC and CVS-75 mode. The main results obtained from this study can be summarized as follows: (1) Periodic calibration of the CPC system is essential because the long-term usage of a CPC leads to an underestimation in the measurements of small particles. (2) Particle emissions measured by the UN-ECE PMP method were found to exhibit comparable repeatability as compared to other regulated emissions. (3) In particle number concentration emitted from different-fueled vehicles, the sources of particle emissions in an ascending order of magnitude are as follows: DPF equipped diesel passenger vehicles, gasoline and LPG fueled vehicles, and DPF unequipped diesel passenger vehicles. Also, we found that the particle numbers of DPF equipped diesel passenger vehicles, gasoline and LPG-fueled vehicles can meet the EU regulation limit (<6.0×1011#/km), while DPF unequipped diesel passenger vehicles do not meet the EU limit.  相似文献   

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