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排序方式: 共有350条查询结果,搜索用时 31 毫秒
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A range of 18 diesel fuels and 21 kerosene fuels from mainly Australian petroleum and synthetic fuel sources, including coal, shale and peat, was investigated. Compositional details were defined as the weight per cent abundances of n-alkanes, branched plus cyclic saturates, single-ring aromatics, doublering aromatics and polynuclear aromatics, using both h.p.l.c. and 13C n.m.r. techniques. Relationships between fuel composition and a range of fuel properties were sought. Simple linear relationships between property values and compositional data were used. Explicit correlative expressions were derived using multiple linear regression analysis, with the coefficient of multiple determination, R2, indicating the quality of the fit between observed and calculated property values. In most cases good correlations were achieved. For diesels the properties investigated, with R2 values in parentheses, were: inverse specific gravity (0.99); 13C n.m.r. aromaticity (0.99); 1H n.m.r. aromaticity (0.88); cetane index (0.97); aniline point (0.96); diesel index (0.98); and FIA-measured aromatics content (0.77). For kerosenes the properties, with R2 values in parentheses, were: 13C n.m.r. aromaticity (0.98); 1H n.m.r. aromaticity (0.97); smoke point (0.88); and FIA-measured aromatics content (0.94). The results are shown to be of value in assessing the potential and limitations of hydrotreating as a process for upgrading synfuels. 相似文献
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J. L. Le H. C. Bai A. A. Mishunin A. V. Starov 《Combustion, Explosion, and Shock Waves》2003,39(3):292-299
Results of an experimental study of a full scramjet model operating on kerosene, which was performed in an IT-302M hotshot wind tunnel based at the Institute of Theoretical and Applied Mechanics of the Siberian Division of the Russian Academy of Sciences, and an experimental study of a model operating on hydrogen, which was performed in a hotshot wind tunnel with fire heating based at the China Aerodynamic Research and Development Center, are reported. The tests were performed for Mach numbers 5 and 6 for flow parameters close to in-flight conditions. An optimal system for kerosene injection under these conditions was determined, and the thrust characteristics of the engine model were examined. The possibility of controlling kerosene combustion in tests in the short-duration wind tunnel was analyzed, and special features of fuel ignition in a short combustor were considered. Intense combustion of kerosene was achieved with upstream injection of more than 3% of hydrogen, which allowed obtaining effective thrust. The distributions of static pressure and force characteristics of the model in the case of kerosene and hydrogen combustion were compared. 相似文献
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以淀粉、丙烯酰胺(AM)、二甲基二烯丙基氯化铵(DMDAAC)为原料,采用氧化还原引发体系,以煤油作为连续相,通过反相乳液聚合法制备阳离子聚丙烯酰胺絮凝剂。考察了乳化剂种类和用量、引发剂浓度、反应时间及反应温度等因素对单体转化率、聚合物特性黏数及接枝率、接枝效率的影响,以及阳离子单体用量对聚合物特性黏数的影响。确定最佳工艺条件为:乳化剂质量分数6%,两种单体共占水相质量分数45%,阳离子单体占总单体的质量分数为30%,引发温度45℃,引发时间4h。在此条件下,单体转化率可达97.82%,特性黏数为340.21mL/g,接枝效率为97.93%。 相似文献
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Ali Barati-Harooni Jamshid Moghadasi Bahman Moslemi 《Petroleum Science and Technology》2017,35(18):1814-1821
The gas holdup is an important parameter that is needed for design and development of surface facilities and transportation pipelines in the field of petroleum engineering. There is no general model for prediction of this parameter in different systems and under different conditions. As a result, development of accurate and general models for prediction of this parameter in various situations is of great importance. This study presents new experimental gas holdup data in the kerosene+CO2 and kerosene+N2 systems. The experimental data were measured by using a bubble column setup. Moreover, a computer-based model namely PSO-ANFIS model is also developed for prediction of the gas holdup in different systems. A total of 818 experimental gas holdup data in various systems were utilized including the newly measured experimental data in the present work as well as experimental data from several published works in the literature. Results showed that the developed PSO-ANFIS model is accurate for prediction of experimental data with an R2 value of 0.998 and average absolute relative deviation (AARD%) of 3.4%. 相似文献
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Zhang Kai Song Feilong Jin Di Xu Shida Sun Jiulun Huang Shengfang 《International Journal of Hydrogen Energy》2021,46(13):9019-9029
To improve the quality of pre-combustion cracking gas, the gliding arc discharge plasma is adopted in this paper. The influence of incoming flow rate, electrode gap distance and discharge frequency on cracking effect have been experimentally studied. The results show that through plasma cracking, the concentration of H2 increases while the concentration of CH4 and C2H4 decrease. With different fuel ratio conditions, the variation trend of C/H ratio as well as the mass flow of carbon and hydrogen atoms in the cracking products vary from each other. The cracking effect becomes weaker with the increase of incoming flow rate, while is better when the fuel ratio is larger. Given the flow rate of 18slpm and 24slpm, the best cracking effect can be acquired with the electrode gap of 1.5 mm. Besides, the effect of gliding arc discharge plasma cracking is weakened as the discharge frequency rises. 相似文献