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81.
多喷嘴对置式气化炉的炉顶封堵砖——炉口塞严重制约着气化炉的长周期运行,通过设计优化提高了炉口塞的寿命,解决了制约气化炉运行周期的问题。 相似文献
82.
Abstract The computational fluid dynamics technique is used to study the behavior of high-pressure natural gas when it flows through nozzles with supersonic velocities. Effect of nozzle geometry is discussed by inserting a constant area channel between the convergent and divergent parts of the system. Various conduit lengths are analyzed to show how the minimum temperature could be influenced by the geometry of the nozzle. The results also show that changing channel length can affect the position of shockwave. The results for the effect of vorticity on the performance of the nozzles show that, although losses in pressure increase due to inlet swirl flow, vorticity increases very sharply in the vicinity of the shock. It could be concluded that the region just before the shock spot is the main region where fine particles can be separated because of the large vorticity strength. Shock with reasonable strength may be favored in practical applications where fine particles separation is desired. 相似文献
83.
浸入式水口结构与工艺参数配合优化的物理模拟 总被引:1,自引:0,他引:1
以鞍钢二炼钢厂小方坯连铸机为原型进行浸入式水口(SEN)结构参数、连铸操作工艺参数配合优化的物理模拟实验,得到了适合鞍钢二炼钢厂生产需要的SEN结构参数和操作工艺参数,在此基础上分析了SEN的结构参数与操作工艺参数对结晶器内钢液流动状况的影响. 相似文献
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Dipl.‐Ing. Sebastian Gepp Dipl.‐Ing. Thomas Ottnad Dipl.‐Ing. Oliver Kessling Dr. Franz Irlinger Prof. Dr. Tim C. Lüth 《化学,工程师,技术》2011,83(4):552-557
The mass flow rate of polypropylene melts through micro nozzles with diameters smaller than 500 μm has been investigated in terms of pressure dependency. The measurements show an exponential influence of pressure and nozzles' diameter on the resulting mass flow rate. The measured data does not correlate with the used power law model which is therefore not applicable for simulating polymer melt extrusion through micro nozzles. 相似文献
86.
在众多管道失效形式中,长输石油管道盗孔现象尤为普遍。这些被打孔盗油的管道需要修复或者更换。尽管目前管道修复提倡采用非焊接的方法,但这类非焊接的修复方法只适用于管壁未穿透的缺陷。在管壁被穿透的情况下,只能采用焊接的方法修复。现场焊接修复打孔管道的方式有两种:接管和补板。运用ANSYS软件对两种修复方法进行有限元分析,结果表明,接管或补板的存在使管道修复结构应力分布不均匀,出现了一定的应力集中;两种修复结构整体的极限裁荷相近。文章给出了两种修复结构中,不同结构尺寸对于修复结果的影响,并且提出了修复建议,对于实际打孔管道修复有一定的参考价值。 相似文献
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M. Jaeschke P. Schley R. Janssen–van Rosmalen 《International Journal of Thermophysics》2002,23(4):1013-1031
This paper gives a brief overview of existing energy measurement systems for natural gas and presents a novel correlative concept for determining the energy contained in a gas. In addition, it provides information on the development and application of a new fundamental reference equation of state. This equation greatly improves prediction of caloric properties and therefore allows optimization of the use of critical nozzles for metering natural gas flows of varying qualities. Laboratory tests of the new energy measurement system have shown that the target uncertainty of 0.2% for the calorific value is routinely reached. A feasibility study currently underway examines the possibility of building a reference calorimeter with an uncertainty of 0.05%. 相似文献
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90.
Low flow water hose reel systems have been proposed for shipboard use. Where water delivery rates are limited, judgment must be used to determine minimum acceptable hose pressure and flow. Laboratory experiments were conducted to quantify differences in fire extinguishing capability for varying pressure and flow. Having established a baseline design, full scale fire fighting tests were conducted that integrated human response and protective equipment variables. 相似文献