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1.
Results are presented on tests on a single-cylinder direct-injection engine operating on diesel fuel, jatropha oil, and blends of diesel and jatropha oil in proportions of 97.4%/2.6%; 80%/20%; and 50%/50% by volume. The results covered a range of operating loads on the engine. Values are given for the chemical and physical properties of the fuels, brake specific fuel consumption, brake power, brake thermal efficiency, engine torque, and the concentrations of carbon monoxide, carbon dioxide and oxygen in the exhaust gases. Carbon dioxide emissions were similar for all fuels, the 97.4% diesel/2.6% jatropha fuel blend was observed to be the lower net contributor to the atmospheric level. The trend of carbon monoxide emissions was similar for the fuels but diesel fuel showed slightly lower emissions to the atmosphere. The test showed that jatropha oil could be conveniently used as a diesel substitute in a diesel engine. The test further showed increases in brake thermal efficiency, brake power and reduction of specific fuel consumption for jatropha oil and its blends with diesel generally, but the most significant conclusion from the study is that the 97.4% diesel/2.6% jatropha fuel blend produced maximum values of the brake power and brake thermal efficiency as well as minimum values of the specific fuel consumption. The 97.4%/2.6% fuel blend yielded the highest cetane number and even better engine performance than the diesel fuel suggesting that jatropha oil can be used as an ignition-accelerator additive for diesel fuel.  相似文献   

2.
Y.D. Bao  Y. He   《Renewable Energy》2006,31(11):1789-1798
This study was undertaken to obtain the knowledge necessary for reducing noise of mixed oil composed of rapeseed oil and conventional diesel oil and for improving the performance of engine fuelled by the mixture. A S195 (8.8 kW) type single-cylinder diesel engine was used to determine the effect of four adjustable working parameters, i.e. intake-valve-closing angle (α), exhaust-valve-opening angle (β), fuel delivery angle (θ) and injection pressure (P, in 104 Pa) on noise when an oil mixture of 30% rapeseed oil and 70% diesel oil was used. Single-factor and multi-factor quadratic regressive orthogonal design test method were adopted in the experiments to find the relationship between noise and four adjustable working parameters. Relationship between these parameters and noise was analysed under two typical operating conditions and mathematical equations characterizing the relationship were formulated. The equation of noise from the regressive test under each operating condition was set as the objective function and the ranges for the four adjustable working parameters were the given constraint condition. Models of nonlinear programming were then constructed. Computer-aided optimization of the working parameters for 30:70 rapeseed oil/diesel oil mixed fuel was achieved. Field test verified that the engine (in use) working condition was found to be bad at maladjustment. The optimum working parameters for two working conditions of the engine were used to adjust the four working parameters. Test results showed that optimum adjustment could achieve noise reduction between 2 and 4 dB and that the power could be increased by 0.6–1.8 kW. The experimental results also provided useful reference material for selection of the most preferable combination of working parameters.  相似文献   

3.
Performance of direct-injection off-road diesel engine on rapeseed oil   总被引:2,自引:0,他引:2  
This article presents the comparative bench testing results of a naturally aspirated, four stroke, four cylinder, water cooled, direct injection Diesel engine operating on Diesel fuel and cold pressed rapeseed oil. The purpose of this research is to study rapeseed oil flow through the fuelling system, the effect of oil as renewable fuel on a high speed Diesel engine performance efficiency and injector coking under various loading conditions.Test results show that when fuelling a fully loaded engine with rapeseed oil, the brake specific fuel consumption at the maximum torque and rated power is correspondingly higher by 12.2 and 12.8% than that for Diesel fuel. However, the brake thermal efficiency of both fuels does not differ greatly and its maximum values remain equal to 0.37–0.38 for Diesel fuel and 0.38–0.39 for rapeseed oil. The smoke opacity at a fully opened throttle for rapeseed oil is lower by about 27–35%, however, at the easy loads its characteristics can be affected by white coloured vapours.Oil heating to the temperature of 60 °C diminishes its viscosity to 19.5 mm2 s−1 ensuring a smooth oil flow through the fuel filter and reducing the brake specific energy consumption at light loads by 11.7–7.4%. Further heating to the temperature of 90 °C offers no advantages in terms of performance. Special tests conducted with modified fuel injection pump revealed that coking of the injector nozzles depends on the engine performance mode. The first and second injector nozzles that operated on pure oil were more coated by carbonaceous deposits than control injector nozzles that operated simultaneously on Diesel fuel.  相似文献   

4.
Conventional fuels used for supplying internal combustion piston engines include petrols and diesel oils produced from petroleum. These are a non-renewable energy source. The environmental policy of the European Union is geared towards increasing the share of renewable fuels in the overall energy consumption. An alternative fuel originating from a renewable source, which could be used for feeding self-ignition internal combustion engines are the fatty acid methyl esters (FAME) of plant oils. The paper reports selected results of testing a 1.3 MULTIJET SDE 90 PS self-ignition engine with the Common Rail reservoir feed system supplied with mixtures of diesel oil and rape oil fatty acid methyl esters (FAME). Tests were carried out on an engine test bed equipped with an eddy-current brake. The purpose of the tests was to determine the economic–energy and ecological indices of engine operation. The concentrations of exhaust gas gaseous components were measured using a MEXA-1600DEGR analyzer, while the particulate concentrations, with a MEXA-1230PM analyzer. In addition, the variations of working medium pressures in the engine chamber and of fuel pressure upstream the injector were recorded as a function of crankshaft rotation angle using the AVL IndiSmart 612 indication system for this purpose. The physicochemical properties of fuels used in the tests were determined using a fuel analyzer. The obtained testing results made it possible to determine and assess the operation indices of the engine fed with mixtures of diesel oil and rape oil fatty acid methyl esters (FAME) with slightly higher ester contents than the requirements of the currently applicable diesel oil standard.  相似文献   

5.
Alcohols extensively used in internal combustion engines are important renewable and sustainable energy resources from environmental and economical perspectives. Besides, bio production of alcohols decreases consumption of fossil‐based fuels. Although there are many studies with regards to the use of lower alcohols such as methanol and ethanol in internal combustion engines, there are a limited number of investigations with higher alcohols. Higher alcohols such as propanol, n‐butanol, and 1‐pentanol are part of the next generation of biofuels, given they provide better fuel properties than lower alcohols. Biodiesel–higher alcohol blends can be used in diesel engines without any engine modification but need to be tested under various engine conditions with long periods in order to evaluate their impacts on engine performance and environmental pollutants. The objective of this study was to evaluate the effect of using propanol, n‐butanol, and 1‐pentanol in waste oil methyl ester (B100) on engine performance and exhaust emissions of a diesel engine running at different loads (0, 3, 6, and 9 kW) with a fixed engine speed (1800 rpm). Test fuel blends were prepared by adding propanol, n‐butanol, and 1‐pentanol (10 vol.%) into waste oil methyl ester to achieve blends of B90Pr10, B90nB10, and B90Pn10, respectively. According to engine performance and exhaust emissions results, the addition of propanol, n‐butanol, and 1‐pentanol to B100 had the effect of increasing brake specific fuel consumption and exhaust gas temperatures. The brake thermal efficiency (BTE) decreased for B90Pr10 and B90nB10, while B90Pn10 showed a slight increase in BTE as compared with B100. When compared with B100, B90Pr10, B90nB10, and B90Pn10 decreased carbon monoxide emissions at lower loads while it increased slightly at 9 kW load. The decrement in oxides of nitrogen emission was observed at whole loads for B90Pr10, B90nB10, and B90Pn10 compared with B100. When considering all loads, B90Pn10 presented the best mean hydrocarbon emission with a reduction of 45.41%. Copyright © 2016 John Wiley & Sons, Ltd.  相似文献   

6.
Y. He  Y. D. Bao 《Renewable Energy》2003,28(9):1447-1453
This study was undertaken to provide knowledge necessary for raising the thermal efficiency of mixed oil composed of rapeseed oil and conventional diesel oil and for improving the performance of an engine fuelled by the mixture. The experimental results obtained showed that a mixing ratio of 30% rapeseed oil and 70% diesel oil was practically optimal in ensuring relatively high thermal efficiency of engine as well as homogeneity and stability of the oil mixture. Method of quadratic regressive orthogonal design test method was adopted in experiment designed to examine the dependence of specific fuel consumption on four adjustable working parameters when the above –mentioned oil mixture was used. These parameters were: intake-valve-closing angle (α), exhaust-valve-opening angle (β), fuel-delivering angle (θ) and injection pressure (P, in 104 Pa). Relationship between these parameters and specific fuel consumption was analyzed under two typical operating conditions and mathematical equations characterizing the relationship were formulated. The equation of specific fuel consumption derived from the regressive test under each operating condition was set as the objective function and the ranges for the four adjustable working parameters were the given constraint condition. Models of non-linear programming were then constructed. Computer aided optimization of the working parameters for 30:70 rapeseed oil/diesel oil mixed fuel was achieved. It was concluded that the predominant factor affecting the specific fuel consumption was fuel-delivering angle θ, the approximate optimal value of which, in this specific case, was 2–3 degrees in advance of that for engine fuelled by pure diesel oil. The experimental results also provided useful reference material for selection of the most preferable combination of working parameters.  相似文献   

7.
This paper presents results of experiments undertaken to determine the performance of a direct injection (DI) diesel engine fuelled by blends of kiln-produced pyroligneous tar (PT) and diesel. The PT was sourced from Bulgaria where it was produced from a pine feedstock via a traditional kiln method that involves separation of the aqueous pyroligneous acid fraction. The tar is characterized by high carbon concentration, viscosity and high heating value. Although high, at fuel injection temperatures over 120 °C the tar's viscosity is likely to be lower than diesel. Analysis by GC revealed a number of compounds typically extracted from wood-based tar products. Blends containing 20% and 40% PT with diesel were tested in a 4-cylinder, 4-stoke DI diesel engine. The blends are stable and readily formed. Little difference in engine performance relative to diesel was found for 20% PT blends. PT blends (40%) exhibit significantly higher in-cylinder gas temperature and pressure. Ignition delay for both blends is longer than diesel, as is the fuel burn rate during the premixed stage of the combustion. During the diffusion stage of combustion, the fuel burn rate is lower relative to diesel. The performance of engines fuelled by blends containing 40% or more PT could be improved through optimization of engine systems.  相似文献   

8.
《能源学会志》2014,87(1):11-17
A direct injection diesel engine fueled by a diesel/biodiesel blend from waste cooking oil up to B100 (a blend of 100% biodiesel content) indicated a combustion efficiency rise by 1.8% at full load. The soot peak volume fraction was reduced by 15.2%, while CO and HC concentrations respectively decreased by 20 and 28.5%. The physical and chemical delay periods respectively diminished by 1.2 and 15.8% for engine noise to pronounce 6.5% reduction. Injection retarding by 5° reduced NOx to those original levels of B0 (a blend of zero biodiesel content) and combined respective reduction magnitudes of 10 and 7% in CO and HC at 75% load. Increasing the speed reduced CO and HC respectively by 26 and 42% at 2.36 times the droplet average strain rate. By coupling the turbulence model to the spray break-up and chemical kinetics models, increasing the injection pressure simultaneously reduced CO, HC and NOx at 17% exhaust gas recirculation ratio.  相似文献   

9.
An experimental investigation was carried out on a small direct injection (DI) diesel engine, fuelling the engine with 10% (B10), 20% (B20), 30% (B30) and 40% (B40) blending of Koroch seed oil methyl ester (KSOME) with diesel. The performance and combustion characteristics of the engine at various loads are compared and analyzed. The results showed higher brake specific fuel consumption (BSFC) and lower brake thermal efficiency (BTE) for the KSOME blends. The engine indicated power (IP) was more for the blends up to B30, but found to be reduced for the blend B40 when compared to that of diesel. The engine combustion parameters such as pressure crank angle diagram, peak pressure, time of occurrence of peak pressure, net heat-release rate, cumulative heat release, ignition delay and combustion duration were computed. The KSOME blends exhibited similar combustion trend with diesel. However, the blends showed an early start of combustion with shorter ignition delay period. The study reveals the suitability of KSOME blends up to B30 as fuel for a diesel engine mainly used in generating sets and the agricultural applications in India without any significant drop in engine performance.  相似文献   

10.
In this study, performance and emissions of cottonseed oil methyl ester in a diesel engine was experimentally investigated. For the study, cottonseed oil methyl ester (CSOME) was added to diesel fuel, numbered D2, by volume of 5%(B5), 20%(B20), 50%(B50) and 75%(B75) as well as pure CSOME (B100). Fuels were tested in a single cylinder, direct injection, air cooled diesel engine. The effects of CSOME-diesel blends on engine performance and exhaust emissions were examined at various engine speeds and full loaded engine. The effect of B5, B20, B50, B75, B100 and D2 on the engine power, engine torque, bsfc's and exhaust gasses temperature were clarified by the performance tests. The influences of blends on CO, NOx, SO2 and smoke opacity were investigated by emission tests. The experimental results showed that the use of the lower blends (B5) slightly increases the engine torque at medium and higher speeds in compression ignition engines. However, there were no significant differences in performance values of B5, B20 and diesel fuel. Also with the increase of the biodiesel in blends, the exhaust emissions were reduced. The experimental results showed that the lower contents of CSOME in the blends can partially be substituted for the diesel fuel without any modifications in diesel engines.  相似文献   

11.
Diesel engines provide the major power source for transportation in the world and contribute to the prosperity of the worldwide economy. However, recent concerns over the environment, increasing fuel prices and the scarcity of fuel supplies have promoted considerable interest in searching for alternatives to petroleum based fuels. Based on this background, the main purpose of this investigation is to evaluate clove stem oil (CSO) as an alternative fuel for diesel engines. To this end, an experimental investigation was performed on a four-stroke, four-cylinder water-cooled direct injection diesel engine to study the performance and emissions of an engine operated using the CSO–diesel blended fuels. The effects of the CSO–diesel blended fuels on the engine brake thermal efficiency, brake specific fuel consumption (BSFC), specific energy consumption (SEC), exhaust gas temperatures and exhaust emissions were investigated. The experimental results reveal that the engine brake thermal efficiency and BSFC of the CSO–diesel blended fuels were higher than the pure diesel fuel while at the same time they exhibited a lower SEC than the latter over the entire engine load range. The variations in exhaust gas temperatures between the tested fuels were significant only at medium speed operating conditions. Furthermore, the HC emissions were lower for the CSO–diesel blended fuels than the pure diesel fuel whereas the NOx emissions were increased remarkably when the engine was fuelled with the 50% CSO–diesel blended fuel.  相似文献   

12.
The performance, emission and combustion characteristics of a single cylinder four stroke variable compression ratio multi fuel engine when fueled with waste cooking oil methyl ester and its 20%, 40%, 60% and 80% blends with diesel (on a volume basis) are investigated and compared with standard diesel. The suitability of waste cooking oil methyl ester as a biofuel has been established in this study. Bio diesel produced from waste sun flower oil by transesterification process has been used in this study. Experiment has been conducted at a fixed engine speed of 1500 rpm, 50% load and at compression ratios of 18:1, 19:1, 20:1, 21:1 and 22:1. The impact of compression ratio on fuel consumption, combustion pressures and exhaust gas emissions has been investigated and presented. Optimum compression ratio which gives best performance has been identified. The results indicate longer ignition delay, maximum rate of pressure rise, lower heat release rate and higher mass fraction burnt at higher compression ratio for waste cooking oil methyl ester when compared to that of diesel. The brake thermal efficiency at 50% load for waste cooking oil methyl ester blends and diesel has been calculated and the blend B40 is found to give maximum thermal efficiency. The blends when used as fuel results in reduction of carbon monoxide, hydrocarbon and increase in nitrogen oxides emissions.  相似文献   

13.
K Pramanik   《Renewable Energy》2003,28(2):239-248
In the present investigation the high viscosity of the jatropha curcas oil which has been considered as a potential alternative fuel for the compression ignition (C.I.) engine was decreased by blending with diesel. The blends of varying proportions of jatropha curcas oil and diesel were prepared, analyzed and compared with diesel fuel. The effect of temperature on the viscosity of biodiesel and jatropha oil was also studied. The performance of the engine using blends and jatropha oil was evaluated in a single cylinder C.I. engine and compared with the performance obtained with diesel. Significant improvement in engine performance was observed compared to vegetable oil alone. The specific fuel consumption and the exhaust gas temperature were reduced due to decrease in viscosity of the vegetable oil. Acceptable thermal efficiencies of the engine were obtained with blends containing up to 50% volume of jatropha oil. From the properties and engine test results it has been established that 40–50% of jatropha oil can be substituted for diesel without any engine modification and preheating of the blends.  相似文献   

14.
In this investigation, castor methyl ester (CME) was prepared by transesterification using potassium hydroxide (KOH) as catalyst and was used in four stroke, single cylinder variable compression ratio type diesel engine. Tests were carried out at a rated speed of 1500 rpm at different loads. Straight vegetable oils pose operational and durability problems when subjected to long term usages in diesel engines. These problems are attributed to high viscosity, low volatility and polyunsaturated character of vegetable oils. The process of transesterification is found to be an effective method of reducing vegetable oil viscosity and eliminating operational and durability problems. The important properties of methyl ester of castor seed oil are compared with diesel fuel. The engine performance was analysed with different blends of biodiesel and was compared with mineral diesel. It was concluded that the lower blends of biodiesel increased the break thermal efficiency and reduced the fuel consumption. The exhaust gas temperature increased with increasing biodiesel concentration. The results proved that the use of biodiesel (produced from castor seed oil) in compression ignition engine is a viable alternative to diesel.  相似文献   

15.
Vegetable oils and biodiesel have emerged as strong alternative fuels worldwide. However use of new fuels in existing engines leads to issues such as wear of vital moving components, and fuel injection equipment (FIE). It is important to ensure that new alternative fuel does not affect the FIE adversely. In this experimental study, a non-firing engine FIE simulator test rig prototype was developed and 250 h endurance test of FIE was performed with an objective to ensure the long-term compatibility and durability of biofuel blends. The components of FIE such as plunger, nozzle needle, valve, and valve holder were investigated for wear. Test fuels used in this study were Karanja blends (K20, K5), Jatropha blends (J20, J5), Biodiesel blends (B20, B5) and baseline mineral diesel in a non-firing engine FIE simulator. The compatibility of FIE with test fuels in terms of dimensional loss, weight loss and surface texture variations using optical microscopy before and after the endurance test was compared. Biodiesel blends showed relatively lower wear compared to mineral diesel however SVO blends showed no definite trend of the wear results compared to baseline mineral diesel.  相似文献   

16.
One of the primary aims of this experimental investigation is to examine hydroxy-gas enrichment effects on environmentally friendly but performance-reducing alternative fuels such as ethanol and biodiesel. Hydroxy gas is a product of the pure water electrolysis method. Entire HHO system has integrated into engine test rig for this purpose. Two different biodiesohol fuel blend prepared and named by their volumetric compositions. Biodiesohol used to describe biodiesel, ethanol and standard diesel blends. Specific fuel properties are measured and ensured to be in EN590 and EN14214 standards. Experiments were conducted on a single cylinder diesel engine which was fuelled with diesel-biodiesel-ethanol fuel blends those enriched by 1 L per minute HHO gas during the entire tests. All of the experiments performed under full load condition within the range of 1200–3200 rpm engine speed. From the view of performance; brake power, brake specific fuel consumption and thermal efficiency results discussed. Besides, carbon monoxide and nitrogen oxides results measured and presented as exhaust emission. Standard diesel fuel outputs determined as a reference line to analyze the changes. A number of studies have been conducted with fuels used in this experimental study and their mixture in different ratios as well, but an examination of the HHO addition to biodiesel is performed for the first time in this research area of the literature.  相似文献   

17.
Plastics have now become indispensable materials in the modern world and application in the industrial field is continually increasing. The properties of the oil derived from waste plastics were analyzed and found that it has properties similar to that of diesel. Waste plastic oil (WPO) was tested as a fuel in a D.I. diesel engine and its performance characteristics were analysed and compared with diesel fuel (DF) operation. It is observed that the engine could operate with 100% waste plastic oil and can be used as fuel in diesel engines. Oxides of nitrogen (NOx) was higher by about 25% and carbon monoxide (CO) increased by 5% for waste plastic oil operation compared to diesel fuel (DF) operation. Hydrocarbon was higher by about 15%. Smoke increased by 40% at full load with waste plastic oil compared to DF. Engine fueled with waste plastic oil exhibits higher thermal efficiency upto 80% of the full load and the exhaust gas temperature was higher at all loads compared to DF operation.  相似文献   

18.
An experimental investigation has been carried out to analyze the performance and emission characteristics of a compression ignition engine fuelled with Karanja oil and its blends (10%, 20%, 50% and 75%) vis-a-vis mineral diesel. The effect of temperature on the viscosity of Karanja oil has also been investigated. Fuel preheating in the experiments – for reducing viscosity of Karanja oil and blends has been done by a specially designed heat exchanger, which utilizes waste heat from exhaust gases. A series of engine tests, with and without preheating/pre-conditioning have been conducted using each of the above fuel blends for comparative performance evaluation. The performance parameters evaluated include thermal efficiency, brake specific fuel consumption (BSFC), brake specific energy consumption (BSEC), and exhaust gas temperature whereas exhaust emissions include mass emissions of CO, HC, NO and smoke opacity. These parameters were evaluated in a single cylinder compression ignition engine typically used in agriculture sector of developing countries. The results of the experiment in each case were compared with baseline data of mineral diesel. Significant improvements have been observed in the performance parameters of the engine as well as exhaust emissions, when lower blends of Karanja oil were used with preheating and also without preheating. The gaseous emission of oxide of nitrogen from all blends with and with out preheating are lower than mineral diesel at all engine loads. Karanja oil blends with diesel (up to 50% v/v) without preheating as well as with preheating can replace diesel for operating the CI engines giving lower emissions and improved engine performance.  相似文献   

19.
This paper presents the results of experimental work carried out to evaluate the combustion performance and exhaust emission characteristics of turpentine oil fuel (TPOF) blended with conventional diesel fuel (DF) fueled in a diesel engine. Turpentine oil derived from pyrolysis mechanism or resin obtained from pine tree dissolved in a volatile liquid can be used as a bio-fuel due to its properties. The test engine was fully instrumented to provide all the required measurements for determination of the needed combustion, performance and exhaust emission variables. The physical and chemical properties of the test fuels were earlier determined in accordance to the ASTM standards.ResultsIndicated that the engine operating on turpentine oil fuel at manufacture's injection pressure – time setting (20.5 MPa and 23° BTDC) had lower carbon monoxide (CO), unburned hydrocarbons (HC), oxides of nitrogen (NOx), smoke level and particulate matter. Further the results showed that the addition of 30% TPOF with DF produced higher brake power and net heat release rate with a net reduction in exhaust emissions such as CO, HC, NOx, smoke and particulate matter. Above 30% TPOF blends, such as 40% and 50% TPOF blends, developed lower brake power and net heat release rate were noted due to the fuels lower calorific value; nevertheless, reduced emissions were still noted.  相似文献   

20.
The present study describes the emission analysis of different blends of karanja oil and diesel with producer gas in dual fuel mode using a twin-cylinder diesel engine in two cases of operations. In case 1, the above fuels are tested in single mode and in dual fuel mode operation at an optimum gas flow rate of 21.49 Kg/h under different load conditions. Similarly, in case 2 the same test fuels are used in dual fuel mode only at an optimum load of 10 kW under different gas flow rates. The study reveals that dual fuel operation of all test fuels shows lower smoke and oxide of nitrogen emissions compared to their single mode operation, whereas other emission parameters are on the higher side. However, all blended fuels show better emissions compared to diesel in both cases of operations.  相似文献   

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