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82.
利用Excel表格进行供暖系统计算 总被引:2,自引:0,他引:2
利用Excel表格进行供暖工程设计计算,可以减少工作量,提高工作效率。介绍了房间热负荷和供暖管道水力计算方法。 相似文献
83.
84.
Employing the density functional theory, we investigate the tensile and fracture processes of the Al/TiN(0 0 1) interface. The simulation presents directly the strain–stress relationship, the ideal tensile strength and the process of bond breaking of the system. Through the analysis of deformation, we find that the softer Al layers deform larger than the harder TiN layers during the tensile process. And fracture occurs between the interface and the sub-interface Al layers. In addition, the results show that during the tensile process, the ripple of the interfacial TiN layer decreases gradually with the increment of the strain. Charge transfer was detected from the Al to TiN layers near the interface area during the tensile process by means of charge density and density of states analyses. The charge transfer affects the fracture process. Compared to our previous study of the Al/TiN(1 1 1) interface, the Al/TiN(0 0 1) interface has smaller work of adhesion and larger tensile strength than the Al/TiN(1 1 1) interface. Our investigation shows that the fractures of the Al/TiN(0 0 1) and (1 1 1) interface systems both happen in the Al layers near the interface. 相似文献
85.
86.
赵新国 《石油地球物理勘探》1992,27(4):545-555
断块油田的油气聚集和分布,在很大程度上受各种类型的断层所控制。这种油田具有构造面貌复杂、含油层系多、油水关系复杂、含油丰度差别大等特点,给油气勘探和开发造成了许多困难和不便。目前,有关断块构造圈闭的统计尚无统一标准。以往所用的取值方法是沿用背斜圈闭的要素统计方法,不能适用于复杂的断块构造圈闭。本文以断层圈闭特点为基础,以影响圈闭性能的各种因素间的函数关系为依据,提出了具有较厚盖层和储层地区的断层圈闭要素的计算方法。将此法应用于东濮凹陷,取得了较高精度的含油圈闭面积。 相似文献
87.
A centrifugal partition chromatograph (CPC) was used as a liquid-liquid catalytic reactor for the isomerisation of hexen-3-ol into ethylpropylketone with a water soluble rhodium catalyst. Global mass transfer coefficients were measured and shown to depend on both the nature of the solute and the flow rate. Liquid-liquid partition isotherms were also determined with the CPC using elution chromatography. Finally, a reactor model was derived to account for the experimental results obtained both under stationary and transient (pulse) conditions. A parameter sensitivity evaluation is also presented. 相似文献
88.
翻领成型器领口曲线的程序计算展开法 总被引:2,自引:2,他引:0
根据翻领成型器领口曲线的数学模型,介绍一种利用计算器复杂公式存贮的特殊功能,预编程序计算相关参数。然后画领口曲线展开图的方法。 相似文献
89.
90.
A study on the prediction of heat transfer coefficient (HTC) and pressure drop of refrigerant mixtures is reported. HTCs and pressure drops of prospective mixtures to replace R12 and R22 are predicted on the same cooling capacity basis. Results indicate that nucleate boiling is suppressed at qualities greater than 20.0% for all mixtures and evaporation becomes the main heat transfer mechanism. For the same capacity, some mixtures containing R32 and R152a show 8.0–10.0% increase in HTCs. Some mixtures with large volatility difference exhibit as much as 55.0% reduction compared with R12 and R22, caused by mass transfer resistance and property degradation due to mixing (32.0%) and reduced mass flow rates (23.0%). Other mixtures with moderate volatility difference exhibit 20.0–30.0% degradation due mainly to reduced mass flow rates. The overall impact of heat transfer degradation, however, is insignificant if major heat transfer resistance exists in the heat transfer fluid side (air system). If the resistance in the heat transfer fluid side is of the same order of magnitude as that on the refrigerant side (water system), considerable reduction in overall HTC of up to 20% is expected. A study of the effect of uncertainties in transport properties on heat transfer shows that transport properties of liquid affect heat transfer more than other properties. Uncertainty of 10.0% in transport properties causes a change of less than 6% in heat transfer prediction. 相似文献