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61.
62.
Rolling large- diameter hardened steel balls over the surface of high- permeability grain- oriented electri-cal steel allows
lines of plastic deformation to be laid down. Choice of proper Young’s modulus and ball diameter enables artificial grain
boundaries to be created, producing appropriate domain refinement and loss reduction. 相似文献
63.
本文介绍了化工原理的课程设计教材——《常用化工单元设备的设计》(新版)的内容编排,阐述了该教材的原版和新版的主要特点。 相似文献
64.
Economically usable water resources per capita are decreasing due to excessive population increase each year in Turkey. For this reason, new water resources should be found in the near future. The potential water resources are seawater or well water both of which need removal of salinity. The most promising treatment method for salinity is reverse osmosis. While reverse osmosis becomes widespread, the cost of the process will decrease. There is no detailed information about cost of seawater desalination in Turkey. In this study, a cost analysis of seawater desalination in Turkey was performed for reverse osmosis systems. The basic parameters of cost analysis such as capacity, recovery, membrane life, energy, chemical costs and flux were evaluated based on the effects on capital, operating and total production costs. 相似文献
65.
An empirical method was developed to study the dynamic mixing characteristics of a single-screw extrusion process. The method
basically involved a modified version of the visible extruder developed by Wong et al. (Plast Rubb Comp Proc Appl 26:78, 1997). Digitized films of the molten polymer web emerging from the slit flow cells attached to the “windows” of the visible extruder’s
barrel were captured in bitmap file format. Subsequent statistical analysis (largely variance) on the pixel intensity of the
cropped films had made quantification of mixing quality possible. The higher the average variance of the pixel intensity,
the poorer the mixing quality. The focus of this investigation was on the effects of temperature and screw speed. For the
selected single-flighted conventional screw, it was found that, in general, the higher the screw speed, the shorter the residence
time and, hence, poorer mixing quality. High screw speed also generated erratic average variance data. The results suggested
that a critical screw speed for optimized mixing might have been present. For the equipment used in the current project, this
critical screw speed lied between 50 and 80 rpm. However, unlike screw speed, melt temperature alone appeared to have relatively
little effect on the mixing quality during extrusion. 相似文献
66.
The jet breakup and droplet formation mechanism of a liquid in the near-critical conditions of a solvent-antisolvent system is examined with high-speed visualization experiments and simulated using a front tracking/finite volume method. The size of droplets formed under varying system pressure at various jet breakup regimes is measured with a Global Sizing Velocimetry, using the shadow sizing method. A stainless steel nozzle with 0.25 mm I.D and 1.6 mm O.D was used in this study. Experiments were performed at fixed temperature of 35 °C and system pressure in the range from 61 to 76 bar in the near-critical regime of the DCM-CO2. At the near mixture critical regime for DCM-CO2 mixture, the miscibility between the two fluid phases increases and the interfacial tension diminishes. This phase behavior has important applications in particle formation using gas antisolvent (GAS) and supercritical antisolvent (SAS) processes. The jet breakup and droplet formation in the near-critical regime is strongly dependent on the changes in interface tension and velocity of the liquid phase. An understanding of the droplet formation and jet breakup behavior of DCM-CO2 in this regime is useful in experimental design for particle fabrication using SAS method. 相似文献
67.
68.
在掌握储层流动单元概念的基础上,系统总结了目前划分储层流动单元的各种方法。综合运用多学科理论,对我国东部某复杂断块油田应用聚类分析法找到了划分流动单元的有效参数和定量界限,并在该断块整套储层中定量划分出四套流动单元,它们各自具有不同的岩性和储层物性。综合研究流动单元类型与剩余油分布的密切关系,揭示了该断块油田流动单元类型与剩余油分布的关系。 相似文献
69.
70.
多学科油藏研究一体化平台是基于Windows操作系统、以局域网络为传输通道、以开发数据库和精细地质研究成果为基础的多学科工作平台。本文扼要介绍了平台的研发背景、总体思路、开发环境,详细描述了数据共享、精细地质建模、精细油藏数值模拟及三维可视化的功能设计与实现方法,最后客观评价了平台的优势与不足。 相似文献