The Experts below are selected from a list of 81177 Experts worldwide ranked by ideXlab platform
Selahaddin Orha Akansu - One of the best experts on this subject based on the ideXlab platform.
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the effect of hydrogen on the performance and emissions of an si Engine having a high compression ratio fuelled by compressed natural gas
International Journal of Hydrogen Energy, 2017Co-Authors: Selim Tangoz, Nafiz Kahrama, Selahaddin Orha AkansuAbstract:Abstract The aim of this paper is investigation of the effect of hydrogen on Engine performance and emissions characteristics of an SI Engine, having a high compression ratio, fuelled by HCNG (hydrogen enriched compressed natural gas) blend. The experiments were carried out at 1500, 2000 and 2500 rpm under full load conditions of a modified Isuzu 3.9 L Engine, having a compression ratio of 12.5. The Engine brake power, brake thermal efficiency, combustion analysis and emissions parameters were realized at 5, 10 15 and 20 deg. CA BTDC (crank angle before top dead center) ignition timings and in excess air ratios of 0.9–1.3 fuelled by hydrogen enriched compressed natural gas (100/0, 95/5, 90/10 and 80/20 of % natural gas/hydrogen). The experimental results showed that the maximum power values were generally obtained with HCNG5 (5% hydrogen in natural gas) fuel. The optimum ignition timing that was obtained according to the maximum brake torque was retarded by the addition of hydrogen to CNG (compressed natural gas), while it was advanced by increasing the Engine Speed. Furthermore, it was observed that the BTE (brake thermal efficiency) generally declined with the hydrogen addition to compressed natural gas and increasing the Engine Speed. Additionally, the curves of cylinder pressure and ROHR (rate of heat release values) generally closed to top dead center with the increasing of the hydrogen fraction in the blend and a decreasing Engine Speed. The hydrocarbon and carbon monoxide emissions generally obtained were lower than the Euro-5 and Euro-6 standards.
S K Chou - One of the best experts on this subject based on the ideXlab platform.
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effects of piston bowl geometry on combustion and emission characteristics of biodiesel fueled diesel Engines
Fuel, 2014Co-Authors: Jing Li, Wenming Yang, Hui An, Amin Maghbouli, S K ChouAbstract:This paper presents the numerical study of the effects of piston bowl geometry on combustion and emission characteristics of a diesel Engine fueled with biodiesel under medium load condition. Three different bowl geometries namely: Hemispherical Combustion Chamber (HCC), Shallow depth Combustion Chamber (SCC), and the baseline Omega Combustion Chamber (OCC) were created with the same compression ratio of 18.5. To simulate the combustion process, computational fluid dynamics (CFD) modeling based on KIVA-4 code was performed. Moreover, CHEMKIN II code was integrated into the KIVA-4 code as the chemistry solver to incorporate detailed chemical kinetics mechanisms consisting of 69 species and 204 reactions for the biodiesel combustion, thereby improving the accuracy of the simulation. It is found that the narrow entrance of combustion chamber could generate a strong squish, especially at high Engine Speed, hence enhancing the mixing of air and fuel. Also, the simulation results indicate that in terms of performance SCC is favorable at low Engine Speed; whereas at high Engine Speed, OCC is preferred. As a consequence, SCC will generate relatively higher NO compared to other two piston bowl designs at low Engine Speed condition. Similarly, the high performance of OCC bowl geometry could result in a high NO emission at high Engine Speed condition.
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performance combustion and emission characteristics of biodiesel derived from waste cooking oils
Applied Energy, 2013Co-Authors: Hui An, Jing Li, Wenming Yang, Amin Maghbouli, S K Chou, K J ChuaAbstract:An experimental study was conducted on a Euro IV diesel Engine to evaluate the performance, combustion and emission characteristics of pure biodiesel and its blend fuels. For each tested fuel, the performance and emissions were measured at four different Engine Speeds (800rpm, 1200rpm, 2400rpm and 3600rpm) under three different loads (25%, 50% and 100% load). The results showed that the use of biodiesel/blend fuels resulted in a higher brake specific fuel consumption, especially at low Engine Speed and partial load conditions. For example, at 25% Engine load, the BSFC was found to be increased by 42% and 34.4% for biodiesel as compared to diesel at 800rpm and 1200rpm respectively. The brake thermal efficiency of biodiesel was found to be slightly higher compared to diesel at 50% and 100% load and the opposite tread was observed at 25% load. For combustion characteristics, a slightly shorter ignition delay and lower peak heat release rate were found for biodiesel compared to pure diesel. With respect to emissions, a slight reduction in the major emissions such as HC and NOx were observed with the use of biodiesel. But the opposite trend was seen at low Engine Speed, revealing that the low Engine Speed had a significant effect on the Engine combustion and emission formation processes.
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experimental investigation of the performance and emission characteristics of direct injection diesel Engine by water emulsion diesel under varying Engine load condition
Applied Energy, 2013Co-Authors: Ebna Alam M Fahd, S K Chou, Yang Wenming, Poh Seng Lee, Christopher YapAbstract:A detailed experimental study has been conducted to evaluate the effect of 10% water emulsion diesel (ED10) on Engine performance and emission, and comparison is made against base diesel fuel. The experiments were performed in a four cylinder 2.5L DI turbocharged Toyota diesel Engine at four different Engine loading conditions (25%, 50%, 75% and 100% load). During experiments, the Engine Speed was varied from 800rpm to 3600rpm in steps of 400rpm for each load condition. Results of in-cylinder pressure traces, heat release rate, Engine power output, brake thermal efficiency and brake specific fuel consumption is presented as Engine performance parameters while measurement of exhaust gas temperature, nitric oxide (NO) and carbon mono-oxide (CO) output is reported as emission parameters. It is noted that ED10 has the ability to produce comparable in-cylinder pressure and heat release rate like base diesel fuel. It is also found that ED10 produces slightly less Engine power output with higher brake specific fuel consumption (BSFC). In addition, lower exhaust gas temperature and lower NO emission is experienced at all load and Engine Speed condition for ED10 as compared to diesel fuel. Although diesel Engines are not prone to higher CO emission at medium to high Engine load, it is found that ED10 suffers from higher CO emission at low load and low Engine Speed condition. However, at higher Engine Speed for a particular load, the CO emission reduces significantly. The comprehensive analysis of the experimental results suggests that ED10 has the potential to be considered as a competitive renewable and greener fuel for diesel Engine applications.
Ruifen Zhao - One of the best experts on this subject based on the ideXlab platform.
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carbonyl compound emissions from a heavy duty diesel Engine fueled with diesel fuel and ethanol diesel blend
Chemosphere, 2010Co-Authors: Chonglin Song, Zhuang Zhao, Jinou Song, Lidong Liu, Ruifen ZhaoAbstract:Abstract This paper presents an investigation of the carbonyl emissions from a direct injection heavy-duty diesel Engine fueled with pure diesel fuel (DF) and blended fuel containing 15% by volume of ethanol (E/DF). The tests have been conducted under steady-state operating conditions at 1200, 1800, 2600 rpm and idle Speed. The experimental results show that acetaldehyde is the most predominant carbonyl, followed by formaldehyde, acrolein, acetone, propionaldehyde and crotonaldehyde, produced from both fuels. The emission factors of total carbonyls vary in the range 13.8–295.9 mg (kW h)−1 for DF and 17.8–380.2 mg (kW h)−1 for E/DF, respectively. The introduction of ethanol into diesel fuel results in a decrease in acrolein emissions, while the other carbonyls show general increases: at low Engine Speed (1200 rpm), 0–55% for formaldehyde, 4–44% for acetaldehyde, 38–224% for acetone, and 5–52% for crotonaldehyde; at medium Engine Speed (1800 rpm), 106–413% for formaldehyde, 4–143% for acetaldehyde, 74–113% for acetone, 114–1216% for propionaldehyde, and 15–163% for crotonaldehyde; at high Engine Speed (2600 rpm), 36–431% for formaldehyde, 18–61% for acetaldehyde, 22–241% for acetone, and 6–61% for propionaldehyde. A gradual reduction in the brake specific emissions of each carbonyl compound from both fuels is observed with increase in Engine load. Among three levels of Engine Speed employed, both DF and E/DF emit most CBC emissions at high Engine Speed. On the whole, the presence of ethanol in diesel fuel leads to an increase in aldehyde emissions.
Hu Chen - One of the best experts on this subject based on the ideXlab platform.
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characteristics of carbonyl compounds emission from a diesel Engine using biodiesel ethanol diesel as fuel
Atmospheric Environment, 2006Co-Authors: Xiaobing Pang, Xiaoyan Shi, Shijin Shuai, Hu ChenAbstract:Characteristics of carbonyl compounds (carbonyls) emissions from biodiesel-ethanol-diesel (BE-diesel) were investigated in a Commins-4B diesel Engine and compared with those from fossil diesel. Acetaldehyde was the most abundant carbonyls in the exhaust, followed by formaldehyde, acetone, propionaldehyde and benzaldehyde. Apliphatic carbonyls emitted from BE-diesel were higher than those from diesel fuel, while formaldehyde and aromatic carbonyls were less than those from diesel fuel. Total carbonyls emissions from BE-diesel were 1-12% higher than those from diesel fuel depending on Engine operating conditions. The effects of Engine Speed and load level were also investigated carefully. It was found that total carbonyls emission was in positive correlation with the Engine Speed. During the constant Speed/varying load tests, minimum total carbonyls emission was found at 50% load. Compared with fossil diesel, the BE-diesel was observed to significantly reduce PM emission and increase slightly NO, emission. (c) 2006 Elsevier Ltd. All rights reserved.
Maher A.r. Sadiq Al-baghdadi - One of the best experts on this subject based on the ideXlab platform.
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Effect of compression ratio, equivalence ratio and Engine Speed on the performance and emission characteristics of a spark ignition Engine using hydrogen as a fuel
Renewable Energy, 2004Co-Authors: Maher A.r. Sadiq Al-baghdadiAbstract:Abstract The present energy situation has stimulated active research interest in non-petroleum and non-polluting fuels, particularly for transportation, power generation, and agricultural sectors. Researchers have found that hydrogen presents the best and an unprecedented solution to the energy crises and pollution problems, due to its superior combustion qualities and availability. This paper discusses analytically and provides data on the effect of compression ratio, equivalence ratio and Engine Speed on the Engine performance, emissions and pre-ignition limits of a spark ignition Engine operating on hydrogen fuel. These data are important in order to understand the interaction between Engine performance and emission parameters, which will help Engine designers when designing for hydrogen.
