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1.
This work aims to replace conventional diesel fuel with low and no carbon fuels like ethanol and hydrogen to reduce the harmful emission that causes environmental degradation. Pursuant to this objective, this study investigated the performance, combustion, and emission characteristics of the diesel engine operated on dual fuel mode by ethanol-diesel blends with H2 enriched intake air at different engine loads with a constant engine speed of 1500 rpm. The results were compared to sole diesel operation with and without H2 enrichment. The ethanol/diesel was blended in v/v ratios of 5, 10, and 15% and tested in a diesel engine along with a 9 lpm H2 flow rate at the intake manifold. The results revealed that 10% ethanol with 9 lpm H2 combination gives the maximum brake thermal efficiency, which is 1% and 4.8% higher than diesel with and without H2 enrichment, respectively. The brake specific fuel consumption of the diesel-ethanol blends with H2 flow increased with increasing ethanol ratio in the blend. When the ethanol ratio increased from 5 to 10%, in-cylinder pressure and heat release rate were increased, whereas HC, CO, and NOx emissions were decreased. At maximum load, the CO and HC emission of 10% ethanol blend with 9 lpm H2 case decreased by about 50% and 28.7% compared to sole diesel. However, NOx emission of the same blend was 11.4% higher than diesel. From the results, the study concludes that 10% ethanol blended diesel with a 9 lpm H2 flow rate at the intake port is the best dual-fuel mode combination that gives the best engine characteristics with maximum diesel replacement.  相似文献   

2.
Biofuels extracted from non-edible oil is sustainable and can be used as an alternative fuel for internal combustion engines. This study presents the performance, emission and combustion characteristic analysis by using simarouba oil (obtained from Simarouba seed) as an alternative fuel along with hydrogen and exhaust gas recirculation (EGR) in a compression ignition (CI) engine operating on dual fuel mode. Simarouba biofuel blend (B20) was prepared on volumetric basis by mixing simarouba oil and diesel in the proportion of 20% and 80% (v/v), respectively. Hydrogen gas was introduced at the flow rate of 2.67 kg/min, and EGR concentration was maintained at 30% of total air introduction. Performance, combustion and emission characteristics analysis were examined with biodiesel (B20), biodiesel with hydrogen substitution and biodiesel, hydrogen with EGR and were compared with neat diesel operation. Results indicate that BTE of the engine operating with biodiesel B20 was decreased when compared to neat diesel operation. However, introducing hydrogen along with B20 blend into the combustion chamber shows a slight increase in the BTE by 1%. NOx emission was increased to 18.13% with the introduction of hydrogen than that of base fuel (diesel) operation. With the introduction of EGR, there is a significant reduction in NOx emission due to decrease in in-cylinder temperature by 19.07%. A significant reduction in CO, CO2, and smoke emissions were also noted with the introduction of both hydrogen and EGR. The ignition delay and combustion duration were increased with the introduction of hydrogen, EGR with biodiesel than neat diesel operation. Hence, the proposed biodiesel B20 with H2 and EGR combination can be applied as an alternative fuel in CI engines.  相似文献   

3.
The influence of hydrogen enrichment on the dieselengine fueled with diesel and palm biodiesel blend (P20) is investigated in this study. The hydrogen is injected into the intake manifold at different flow rates of 7 lpm and 10 lpm for each loading condition of 30%, 60%, 80%, 90%, and 100%, respectively. Hydrogen enrichment improves the BTE and BSEC due to its high calorific value and decreases emissions like HC, CO, and CO2 due to its carbon-free structure. However, due to a rise in EGT, NOx emission has increased. With the addition of hydrogen, combustion properties such as in-cylinder pressure (ICP), heat release rate (HRR), and ignition delay (ID) improve while the combustion duration (CD) drops. Compared to P20 fuel,P20 + 10H2 has a 28% increase in BTE and a 20% decrease in BSEC at 90% load. Similarly, HC, CO, and CO2 emissions decrease by 16%, 35%, and 12%, while NOx emission increases by 13% compared to P20. At full load, P20 + 10H2increasesin-cylinder pressureand heat release ratebyupto 1–5%, while CD decreases by 12.5% compared to the P20 blend.  相似文献   

4.
Biodiesel either in neat form or as a mixture with diesel fuel is widely investigated to solve the twin problem of depletion of fossil fuels and environmental degradation. The main objective of the present study is to compare performance, emission and combustion characteristics of biodiesel derived from non edible Jatropha oil in a dual fuel diesel engine with base line results of diesel fuel. The performance parameters evaluated were: brake thermal efficiency, brake specific fuel consumption, power output. As a part of combustion study, in-cylinder pressure, rate of pressure rise and heat release rates were evaluated. The emission parameters such as carbon monoxide, carbon dioxide, un-burnt hydrocarbon, oxides of nitrogen and smoke opacity with the different fuels were also measured and compared with base line results. The different properties of Jatropha oil after transestrification were within acceptable limits of standards as set by many countries. The brake thermal efficiency of Jatropha methyl ester and its blends with diesel were lower than diesel and brake specific energy consumption was found to be higher. However, HC, CO and CO2 and smoke were found to be lower with Jatropha biodiesel fuel. NOx emissions on Jatropha biodiesel and its blend were higher than Diesel. The results from the experiments suggest that biodiesel derived from non edible oil like Jatropha could be a good substitute to diesel fuel in diesel engine in the near future as far as decentralized energy production is concerned. In view of comparable engine performance and reduction in most of the engine emissions, it can be concluded and biodiesel derived from Jatropha and its blends could be used in a conventional diesel engine without any modification.  相似文献   

5.
ABSTRACT

In the present research work, the experimental analysis has been executed to investigate the influence of diethyl ether as an oxygenated additive to the diesel-biodiesel blend on the performance, combustion and emission characteristics of a diesel engine. The biodiesel (Frying oil methyl ester) was prepared by the transesterification process, and the biodiesel was added (40% by volume) to the diesel fuel to prepare the diesel-biodiesel blend (D60FME40). The diethyl ether was added to the diesel-biodiesel blends D60FM35 (diesel 60% + biodiesel 35% by volume) and D60FM30 (diesel 60% + biodiesel 30% by volume) with suitable volume proportions of 5% and 10% respectively to form diesel-biodiesel-diethyl ether blends ((D60FM35DEE5) & (D60FM30DEE10)). Initially, the test was conducted with diesel fuel to obtain the baseline reference reading. Then, the reading was compared with results taken from the engine using a diesel-biodiesel blend (D60FME40) and diethyl ether blends (D60FM35DEE5) & (D60FM30DEE10). The results reveal that the maximum brake thermal efficiency was obtained with diesel fuel and it was higher than the diesel-biodiesel blend and diethyl ether blends. The peak in-cylinder gas pressure and heat release rate in the premixed stage was less for the diesel-biodiesel blend, but it was increased with the addition of diethyl ether to the blend. The diesel-biodiesel-diethyl ether blends show less carbon monoxide and hydrocarbon emissions except for NOX emission as compared to the diesel and diesel-biodiesel blend, especially at the engine rated power.  相似文献   

6.
The influence of iron nanoparticle (INP) addition (75 ppm) and hydrogen enrichment (10 lpm) with waste cooking palm biodiesel blend (WCB) on a CRDI diesel engine is evaluated. A blend of 20% WCB and 80% diesel is used, and the dosing level of INP has been kept at 75 ppm, which has been decided based on the oxygen content of biodiesel. Results indicate that the combination of H2 enrichment and INP addition improves the BTE and BSFC of biodiesel blends as that of diesel. A maximum improvement of BTE of 7.1% than that of diesel is obtained at 90% loading. The combined impact of better hydrogen combustion characteristics and improved air-fuel mixing with nanoparticles reduces CO and HC emissions by 37.5% and 41.8%, respectively, for the WCB fuel sample. However, NOX emission shows an elevation of 27.4% compared to diesel. Combustion parameters, namely ICP (80.1 bar) and HRR (89.5 J/˚CA) indicate an improvement of 5.3% and 6.7% compared to diesel for WCB + INP + H2. This is owing to the combination of hydrogen's rapid flame speed and INP-added biodiesel's increased thermal conductivity.  相似文献   

7.
Influence of biodiesel on engine combustion and emission characteristics   总被引:1,自引:0,他引:1  
This paper discusses the influence of biodiesel on the engine combustion characteristics. The considered fuel is neat biodiesel from rapeseed oil. The considered engine is a bus diesel engine with injection M system. The engine characteristics are obtained by experiments and numerical simulation. The results obtained with biodiesel are compared to those obtained with mineral diesel under various operating regimes. In this way, the influences of biodiesel usage on the injection pressure, injection timing, ignition delay, in-cylinder gas pressure and temperature, heat release rate, exhaust gas temperatures, harmful emissions, specific fuel consumption, and on engine power are analyzed. Furthermore, the relationships among fuel properties, injection and combustion characteristics, harmful emissions, and other engine performance are determined. Special attention is given to possible explanations of higher NOx emission in spite of lower in-cylinder gas temperature.  相似文献   

8.
Fuel injection pressure and injection timing are two extensive injection parameters that affect engine performance, combustion, and emissions. This study aims to improve the performance, combustion, and emissions characteristics of a diesel engine by using karanja biodiesel with a flow rate of 10 L per minute (lpm) of enriched hydrogen. In addition, the research mainly focused on the use of biodiesel with hydrogen as an alternative to diesel fuel, which is in rapidly declining demand. The experiments were carried out at a constant speed of 1500 rpm on a single-cylinder, four-stroke, direct injection diesel engine. The experiments are carried out with variable fuel injection pressure of 220, 240, and 260 bar, and injection timings of 21, 23, and 25 °CA before top dead center (bTDC). Results show that karanja biodiesel with enriched hydrogen (KB20H10) increases BTE by 4% than diesel fuel at 240 bar injection pressure and 23° CA bTDC injection timing. For blend KB20H10, the emissions of UHC, CO, and smoke opacity are 33%, 16%, and 28.7% lower than for diesel. On the other hand NOx emissions, rises by 10.3%. The optimal injection parameters for blend KB20H10 were found to be 240 bar injection pressure and 23 °CA bTDC injection timing based on the significant improvement in performance, combustion, and reduction in exhaust emissions.  相似文献   

9.
In the present study, a comparative analysis of enrichment of hydrogen alongside diesel fuel and two different sources of biodiesel namely rice bran oil is an edible oil, and karanja oil being non-edible is tested. Hydrogen at a fixed flow rate of 7 lpm is inducted through the intake manifold. A total of six fuel samples are considered: diesel (D), hydrogen-enriched diesel (D + H2), hydrogen-enriched 10, and 20% rice bran biodiesel blend (RB10 + H2 and RB20 + H2), and hydrogen-enriched 10 and 20% karanja biodiesel blend (KB10 + H2 and KB20 + H2). Results indicate that enrichment of hydrogen improves combustion and results in 2.5% and 1.6% increase in the brake thermal efficiency of diesel fuel and rice bran biodiesel, respectively. For karanja biodiesel the increment is negligible. Fuel consumption of the D + H? is 6.35% lower and for RB10 + H? and KB10 + H? it is decreased by 2.9% and 1.3%, respectively. The Presence of hydrogen shows the 4–38% lower CO emissions and 6–14% lower UHC emission due to better combustion. The blends RB10 + H? and KB10 + H? produce up to 6–13% higher NOx emission and that for the blends RB20 + H? and KB20 + H? it goes up to 25%. Overall rice bran oil is found to provide better performance than karanja biodiesel.  相似文献   

10.
The aim of this study is to determine the availability of pomegranate seed oil biodiesel (POB) as an alternative fuel in diesel engines and evaluate engine performance and emission characteristics of pure hydrogen enriched POB using diesel engine. For this purpose, the intake manifold of the test engine was modified and hydrogen enriched intake air was supplied throughout the experiments. Physical properties of POB and its blend with diesel fuel were also determined. The results showed that measured physical properties of POB are comparable with diesel fuel. According to engine performance experiments, although POB utilization has slight undesirable effects on some engine performance parameters such as brake power output and specific fuel consumption, it can be used as alternative fuel in diesel engines, by this way CO emission can be improved. Finally, hydrogen enrichment experiments indicated that pure hydrogen addition causes a slight improvement in both engine performance and exhaust emissions.  相似文献   

11.
In this study, chicken fat biodiesel with synthetic Mg additive was studied in a single-cylinder, direct injection (DI) diesel engine and its effects on engine performance and exhaust emissions were studied. A two-step catalytic process was chosen for the synthesis of the biodiesel. Methanol, sulphuric acid and sodium hydroxide catalyst were used in the reaction. To determine their effects on viscosity and flash point of the biodiesel, reaction temperature, methanol ratio, type and amount of catalyst were varied as independent parameters. Organic based synthetic magnesium additive was doped into the biodiesel blend by 12 μmol Mg. Engine tests were run with diesel fuel (EN 590) and a blend of 10% chicken fat biodiesel and diesel fuel (B10) at full load operating conditions and different engine speeds from 1800 to 3000 rpm. The results showed that, the engine torque was not changed significantly with the addition of 10% chicken fat biodiesel, while the specific fuel consumption increased by 5.2% due to the lower heating value of biodiesel. In-cylinder peak pressure slightly rose and the start of combustion was earlier. CO and smoke emissions decreased by 13% and 9% respectively, but NOx emission increased by 5%.  相似文献   

12.
Using nonedible waste frying oil (WFO) as biodiesel and hydrogen in the mix composition may partly replace significant quantities of diesel fuel and help reduce fossil fuel reliance. The combination of diesel fuel, waste-fired biodiesel, and hydrogen gas can improve the performance, combustion, and emissions of single-fuel and dual-fuel diesel engines. This may lead to a novel alternative fuel mix pattern and modification for diesel engines, which is the research gap. Although there has been some research on waste-fired biodiesel and hydrogen gas-powered dual-fuel engines with the goal of partly replacing fossil fuels to a larger degree, there has been very little progress in this area. As a result, the current research effort focuses on using diesel fuel (100%, 30%, and 60%), waste-fired biodiesel (at 100%, 70%, and 40%), and hydrogen gas as fuel sources (5 and 10 liters per minute [LPM]). According to the current experiment, it was perceived in both dual-fuel and single-fuel modes. Under duel-fuel mode, the engine results for WFOB70D30 + H10 fuel blend had higher 4.2% (brake thermal efficiency [BTE]), 19.72% (oxides of nitrogen [NOx]), and 9.09% (ignition delay [ID]) with a minimal range of (in-cylinder pressure, MFB, volumetric efficiency and heat release rate [HRR]) and a dropped rate of 4.34% (brake-specific energy consumption [BSEC]), 33.33% (carbon monoxide [CO]), 39.28% (hydrocarbons [HC]), 9.43% (smoke), and 6.97% (combustion duration [CD]) related to diesel fuel at peak load. However, single-fuel powered diesel engines provide minimal performance for the WFOB40D60 fuel blend with (11.32% lower BTE and 2.04% higher BSEC) and minimal rate of combustion (lower cylinder pressure, 2.12% minimal CD, 14.72% higher ID, minimal HRR combustion, volumetric efficiency, and MFB). Emitted fewer emissions (9.09% less CO, 4.87% less HC, 0.92% higher NOx, and 1.69% more smoke) than diesel fuel at peak load. Therefore, it was concluded that adding 10 LPM of hydrogen gas to the biodiesel under a dual-fuel condition leads to better combustion, better performance, and less pollution than the single-fuel mode of operation.  相似文献   

13.
Shortage of non-renewable energies, increase in fossil fuel prices and stricter emissions regulations due to high NOx and soot emissions emitted from combustion of heavy diesel fuels by compression ignition engines, has led consumers to use renewable, cleaner and cheap fuels. An investigation has been computationally carried out to explore the influences of hydrogen and nitrogen addition on engine performance such as indicated power and indicated specific energy consumption and amounts of pollutant emissions like NOx, soot, and CO in an HSDI (High-Speed Direct Injection) diesel engine. Optimized sub-models, such as turbulence model, spray model, combustion model and emissions models have selected for the main CFD code. Meanwhile, HF (Homogeneity Factor) has been employed for analysing in-cylinder air-fuel mixing quality under various addition conditions. After validations with experimental data of diesel combustion with a single addition of 4% hydrogen and combined addition of 6% hydrogen + 6% nitrogen, investigations have conducted for modeling mixing and combustion processes with additions of hydrogen and nitrogen by ranges of 2–8% (v/v). Results showed that a single addition of H2 increased NOx and decreased CO and soot and improved ISEC and IP. In the case of nitrogen addition, NOx decreased, both CO and soot emission increased and ISEC and IP considerably ruined compared with NDC operation. Based on the results obtained for simultaneous addition of N2 (8% of v/v) and H2 (8% of v/v), NOx and soot emissions decreased by 11.5% and 42.5% respectively, and ISEC and IP improved 25.7% and 13%, respectively. But amount of CO emissions had an increase of 52% should be paid necessary attention as a main disadvantage.  相似文献   

14.
柴油机掺烧不同比例生物柴油的试验研究   总被引:21,自引:0,他引:21  
将体积分数为10%2、0%、30%的生物柴油掺混到柴油里组成3种混合燃料,并连同纯柴油共4种燃料,在一台四缸增压中冷柴油机上进行性能、燃烧和排放特性的试验研究.结果表明,柴油机燃用生物柴油与柴油混合燃料的折合油耗率与燃用纯柴油时基本相当;燃用混合燃料的缸内最大爆发压力和压力升高率较低,着火时刻较晚;混合燃料的NOx和碳烟排放与燃用纯柴油时相比均有不同程度的降低,但混合燃料的HC和CO排放只是在1 500r/min时才较纯柴油低,当转速在2 300 r/min时,混合燃料的HC和CO排放更高.  相似文献   

15.
Biofuel (biodiesel, bioethanol) is considered one of the most promising alternative fuels to petrol fuels. The objective of the work is to study the characteristics of the particle size distribution, the reaction characteristics of nanoparticles on the catalyst, and the exhaust emission characteristics when a common rail direct injection (CRDI) diesel engine is run on biofuel-blended diesel fuels. In this study, the engine performance, emission characteristics, and particle size distribution of a CRDI diesel engine that was equipped with a warm-up catalytic converters (WCC) or a catalyzed particulate filter (CPF) were examined in an ECE (Economic Commission Europe) R49 test and a European stationary cycle (ESC) test. The engine performance under a biofuel-blended diesel fuel was similar to that under D100 fuel, and the high fuel consumption was due to the lowered calorific value that ensued from mixing with biofuels. The use of a biodiesel–diesel blend fuel reduced the total hydrocarbon (THC) and carbon monoxide (CO) emissions but increased nitrogen oxide (NOx) emissions due to the increased oxygen content in the fuel. The smoke emission was reduced by 50% with the use of the bioethanol–diesel blend. Emission conversion efficiencies in the WCC and CPF under biofuel-blended diesel fuels were similar to those under D100 fuel. The use of biofuel-blended diesel fuel reduced the total number of particles emitted from the engine; however, the use of biodiesel–diesel blends resulted in more emissions of particles that were smaller than 50 nm, when compared with the use of D100. The use of a mixed fuel of biodiesel and bioethanol (BD15E5) was much more effective for the reduction of the particle number and particle mass, when compared to the use of BD20 fuel.  相似文献   

16.
The effects of biodiesel (rapeseed methyl ester, RME) and different diesel/RME blends on the diesel engine NOx emissions, smoke, fuel consumption, engine efficiency, cylinder pressure and net heat release rate are analysed and presented. The combustion of RME as pure fuel or blended with diesel in an unmodified engine results in advanced combustion, reduced ignition delay and increased heat release rate in the initial uncontrolled premixed combustion phase. The increased in-cylinder pressure and temperature lead to increased NOx emissions while the more advanced combustion assists in the reduction of smoke compared to pure diesel combustion. The lower calorific value of RME results in increased fuel consumption but the engine thermal efficiency is not affected significantly. When similar percentages (% by volume) of exhaust gas recirculation (EGR) are used in the cases of diesel and RME, NOx emissions are reduced to similar values, but the smoke emissions are significantly lower in the case of RME. The retardation of the injection timing in the case of pure RME and 50/50 (by volume) blend with diesel results in further reduction of NOx at a cost of small increases of smoke and fuel consumption.  相似文献   

17.
餐饮废油基生物柴油对柴油机有害排放特性的影响   总被引:1,自引:0,他引:1       下载免费PDF全文
郑轶  陈文  魏小栋  张武高 《柴油机》2018,40(5):7-12
在一台电控共轨增压中冷柴油机台架上,燃用纯柴油以及分别掺混10%、20%、30%餐饮废油制生物柴油的柴油/生物柴油混合燃料,研究生物柴油对柴油机燃烧及排放特性的影响。结果表明:生物柴油使发动机的预喷放热率略微下降,主喷放热率有所升高,缸压峰值随掺混比例的增大略有降低;燃用生物柴油使发动机的NOx排放有所上升,HC排放略有下降,CO排放变化不大;低转速下核模态颗粒排放略微增加,积聚态颗粒数有所减少,高转速下核模态和积聚态颗粒数都减少;掺混生物柴油会增加发动机排气颗粒物的氧化活性,使得最大氧化速率温度降低,活化能降低;掺混生物柴油能够降低颗粒相多环芳烃的质量比排放。  相似文献   

18.
This paper experimentally investigates the influence of hydrogen enrichment on the combustion and emission characteristics of a diesel HCCI engine using a modified Cooperative Fuel Research (CFR) engine. Three fuels, n-heptane and two middle distillates with cetane numbers of 46.6 and 36.6, are studied.The results show that hydrogen enrichment retards the combustion phasing and reduces the combustion duration of a diesel HCCI engine. Besides, hydrogen enrichment increases the power output and fuel conversion efficiency, and improves the combustion stability. However, hydrogen enrichment may narrow the operational compression ratio range and increase the knocking tendency. Both the overall indicated specific CO emissions (isCO) and CO emissions per unit burned diesel fuel mass are reduced by hydrogen enrichment. Although hydrogen enrichment decreases the overall indicated specific unburned hydrocarbon emissions (isHC), it does not significantly affect the HC emissions per unit burned diesel fuel mass.  相似文献   

19.
In this study, the biodiesel produced from soybean crude oil was prepared by a method of alkaline-catalyzed transesterification. The important properties of biodiesel were compared with those of diesel. Diesel and biodiesel were used as fuels in the compression ignition engine, and its performance, emissions and combustion characteristics of the engine were analyzed. The results showed that biodiesel exhibited the similar combustion stages to that of diesel, however, biodiesel showed an earlier start of combustion. At lower engine loads, the peak cylinder pressure, the peak rate of pressure rise and the peak of heat release rate during premixed combustion phase were higher for biodiesel than for diesel. At higher engine loads, the peak cylinder pressure of biodiesel was almost similar to that of diesel, but the peak rate of pressure rise and the peak of heat release rate were lower for biodiesel. The power output of biodiesel was almost identical with that of diesel. The brake specific fuel consumption was higher for biodiesel due to its lower heating value. Biodiesel provided significant reduction in CO, HC, NOx and smoke under speed characteristic at full engine load. Based on this study, biodiesel can be used as a substitute for diesel in diesel engine.  相似文献   

20.
The current research work focus on the utilization of hydrogen as a fuel in CI engine has been increased tremendously, since it is a zero-emission fuel. But higher self-ignition temperature than conventional fuel, makes to operate in dual fuel mode condition in CI engine. The diesel or biodiesel along with hydrogen in a CI engine results in the improvement in the performance but increase of NO. In order to minimize the NO emission, addition of ethanol with jamun B20 biodiesel blend (biodiesel-diesel-ethanol) and two ternary blends such as B20E05 and B20E10 are formed. In the present study, biodiesel along with H2 is admitted in the CI engine. Ethanol addition reduces combustion temperature and act as cetane improver for the biodiesel. This induces better combustion of the fuel and reduce NO. The biodiesel production from jamun seed is carried out through transesterification process. H2 of 4 lpm is allowed at the air inlet and jamun B20 blend is injected through the fuel injector. Improvement of brake thermal efficiency and increase in the NO are observed for the hydrogen with biodiesel operated CI engine. The performance and emission behaviors of CI engine done for the test samples. At full load condition (ternary blend) B20E05 assisted H2 shows the drastic reduction of NO emission of 8.2% than B20 assist H2 blend. In other hand emission like hydrocarbon, carbon monoxide and smoke opacity show a notable reduction for B20E05 blend assist H2 than other test sample fuel. The thermal efficiency is 30.98% for B20E05 assist H2 and it is 7.55% and 4.7% higher than B20 and B20E05 assist H2 blend respectively.  相似文献   

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