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1.
Absorption spectra of several types of diesel fuel are studied experimentally. Index of refraction of these fuels is calculated using subtractive Kramers-Krönig analysis. The ageing process of fuels is simulated by prolonged boiling. Radiative properties of diesel fuel droplets are calculated using the Mie theory and a simplified approach, based on approximations of absorption and scattering efficiency factors. It is pointed out that the accuracy of the simplified approach is sufficient for practical applications in the visible and infrared ranges, for various types of diesel fuel, and for droplet radii in the range from 5 to 50 μm. The monodisperse approximation is shown to be applicable for the analysis of infrared radiative properties of realistic polydisperse diesel fuel sprays. 相似文献
2.
本文分析日产车用PDG型柴油机的结构特点及其缸套穴蚀的形成原因、危害和检查与判断方法,并提出在使用中应采取的预防措施。 相似文献
3.
燃料甲酯应用研究浅析 总被引:1,自引:0,他引:1
本阐述了分别使用燃料甲酯及柴油时由柴油机以加俐到的示功图,烟度及过量空气系统等的对比结果。经分析认为:当燃料甲酯取代柴油机时,用户可不必对柴油机另作调整,因而十分方便。 相似文献
4.
Thermal analysis of a ceramic coating diesel engine piston using 3-D finite element method 总被引:1,自引:0,他引:1
In this study, firstly, thermal analyses are investigated on a conventional (uncoated) diesel piston, made of aluminum silicon alloy and steel. Secondly, thermal analyses are performed on pistons, coated with MgO-ZrO2 material by means of using a commercial code, namely ANSYS. Finally, the results of four different pistons are compared with each other. The effects of coatings on the thermal behaviors of the pistons are investigated. It has been shown that the maximum surface temperature of the coated piston with material which has low thermal conductivity is improved approximately 48% for the AlSi alloy and 35% for the steel. 相似文献
5.
��Ȼ���ƺϳ��ͽ��� 总被引:5,自引:1,他引:4
天然气制合成油得到的柴油燃料基本不含硫和芳烃 ,费—托法合成技术的进步已使天然气制合成油(GTL)的生产成本可与 18~ 2 2美元 /桶的原油价格相竞争 ,因而GTL已成为天然气 ,尤其是偏远地区天然气高效利用的一个有前景的途径。GTL技术由合成气生产、费—托合成和产品精制三部分组成。GTL的工艺方案有埃克森公司AGC - 2 1工艺、壳牌公司SMDS工艺、萨索尔公司Synthol工艺、合成油公司工艺等。GTL技术在合成气生产和费托合成方面还出现了一些新的进展。 2 1世纪将迎来GTL装置新的发展期 ,在未来 15年内 ,预计GTL装置生产能力将增加 (45 0 0~ 6 75 0 )× 10 4 t/a。 2 0 0 5年前将有 7套GTL装置投运 ,总能力 880× 10 4 t/a。 相似文献
6.
P. Balle H. Bockhorn B. Geiger N. Jan S. Kureti D. Reichert T. Schrder 《Chemical Engineering and Processing: Process Intensification》2006,45(12):1065-1073
This study deals with the development of a laboratory bench for the practical evaluation of catalysts that are useful for the direct conversion of NOx and soot in the exhaust of diesel engines. The employed model exhaust is generated by using a diffusion burner with additionally dosing some gaseous components to the burner gas to obtain a realistic feed composition. The produced soot is extensively characterized by employing thermogravimetry, transmission electron microscopy, N2 physisorption and temperature programmed techniques. The results of the different characterization methods show that the present soot is suitable for the intended catalytic investigations. The simultaneous conversion of NOx and soot is examined like in practice, i.e. the soot is separated from the tail gas by a diesel particulate filter (DPF) that is coated with the catalyst. The deposited soot is then catalytically converted by NOx and O2 to form N2 and CO2. The conversions of NOx and soot are measured by exclusively applying gas analysers, whereby a special experimental procedure is developed to determine the soot removal. Hence, additional soot related analytics are not required. To show the suitability of the constructed bench a Pt/Fe2O3/β-zeolite sample is taken as test catalyst that is reported to be very active in NOx/soot reaction. The measurements performed with and without catalyst clearly show the effect of the used sample in simultaneous NOx/soot conversion. We therefore consider the constructed laboratory bench to be a useful tool for testing and ranking catalytic materials. 相似文献
7.
Speciation of the semivolatile hydrocarbon engine emissions from sunflower biodiesel 总被引:1,自引:0,他引:1
Biodiesel fuel is a very attractive alternative to conventional fuel and its effects in the engine performance and regulated emissions have been widely studied. However, the impact on unregulated individual compounds or chemical characteristics of exhaust emissions is not fully characterized. In this paper, the semivolatile fractions of the exhaust emissions of biodiesel blends and conventional fuel have been speciated. The results show great differences between the compounds emitted, especially regarding oxygenated and aromatic species. Likewise, there is a clear relationship between speciated hydrocarbons and other important emissions such as total hydrocarbons (HC), particulate matter (PM), volatile organic fraction (VOF) and mean particle diameter (Dm) of PM. 相似文献
8.
涡轮增压柴油机模拟计算等压法的探讨 总被引:3,自引:0,他引:3
针对有些模拟计算可以忽略排气压力波的影响,提出了等压法计算的设想,这是一种每一工作循环缸外热力过程只计算一次的简化方法。分析结果表明,这种计算可以满足零维模型必须满足的所有制约方程,能真实地模拟涡轮增压柴油机的实际工作过程,适用于各种增压系统,但仍有待于进一步的研究与改进。根据等压法,建立了一种适用于定压涡轮系统的计算模型--“定压涡轮”模型,用于MPC增压系统的计算,计算结果与试验结果基本吻合,与容积法计算结果趋于一致,从而验证了模型的正确性,同时也表明这种缸外计算法是有效的。 相似文献
9.
10.
本文介绍了以悬浮型速溶PHPAM为基础研制的低温油井堵水剂,讨论了影响堵水剂交联时间和成胶粘度的因素,制定了移动式弹性隔板堵水工艺并成功地应用于二连油田蒙古林砾岩油藏的油井堵水。该堵剂适用于30—60℃油井,交联时间可控、配制简便、快速、施工周期短。 相似文献