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81.
高分子量聚合物的分子量对岩心渗透率的适应性研究 总被引:12,自引:2,他引:10
本文通过不同分子量的高分子量聚合物(部分水解聚丙烯酰胺)在不同渗透率岩心中的流动实验,研究了高分子量聚合物的分子量与岩心渗透率之间的匹配关系,为大庆油田采用高分子量聚合物驱油提供决策依据。 相似文献
82.
The axisymmetric Laplace equation is solved numerically to extract contact-angle data for a flat liquid/vapor interface contacting a submerged hemispherical solid. The liquid/vapor interface is treated as a membrane, with a membrane tension equal to the surface energy of the liquid. By measuring the vertical displacement of the membrane and the projected contact area the membrane makes with the hemisphere, the contact angle and correspondingly the driving force for motion of the contact line can be measured. We show that characteristic receding and advancing contact angles can be obtained by measuring the contact radii formed upon initial contact between the interface and hemisphere and final contact just prior to detachment of the interface, respectively. Use of the technique is illustrated with a model experiment involving the contact of an air/water interface with a poly(methyl methacrylate) surface. 相似文献
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84.
用新模型综合评价油田开发效果的探讨 总被引:4,自引:3,他引:1
针对目前各种评价方法常用最大隶属度识别准则不适用性及权重确定问题,在对模糊层次评判和未确知测度模型研究的基础上,以兼顾主观偏好和客观信息的综合赋权法为依据,提出将合理反映主观认知程度的层次分析法和客观反映指标重要性的相似权二者结合起来,通过偏好系数科学合理的确定出评价指标权重,然后尝试用模糊评判模型对油藏进行评价、排序,以标准区间值识别准则代替最大隶属度识别准则,减少误判。该评价方法首次应用于某油区低渗透注水油藏的评价,取得了较好效果。与灰色聚类分析等评价模型比较,具有权重确定合理、识别合理的优点,提高了开发效果综合评价的可信度,对其他驱动类型的油藏开发效果评价具有一定的借鉴作用。 相似文献
85.
The macromolecular structure of coals thermally treated at 35°C, 100°C and 150°C was investigated by dynamic penetrant transport in thin coal sections. The effects of temperature, carbon content in coal, and penetrant type on the transport mechanism were investigated. Dynamic swelling studies showed that penetrant transport into coal is a function of the average molecular weight between crosslinks, Mc. The penetrant transport mechanism at low activity is Fickian diffusion. The transport mechanism deviates from Fickian diffusion to anomalous transport, when the carbon content in coal and penetrant activity increase. Variations of the diffusion coefficients and relaxation constants were determined using a diffusion/relaxation coupled model. 相似文献
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87.
Process optimisation and optimal control of batch and continuous drum granulation processes are studied in this paper. The main focus of the current research has been: (i) construction of optimisation and control relevant, population balance models through the incorporation of moisture content, drum rotation rate and bed depth into the coalescence kernels; (ii) investigation of optimal operational conditions using constrained optimisation techniques; (iii) development of optimal control algorithms based on discretized population balance equations; and (iv) comprehensive simulation studies on optimal control of both batch and continuous granulation processes. The objective of steady state optimisation is to minimise the recycle rate with minimum cost for continuous processes. It has been identified that the drum rotation-rate, bed depth (material charge), and moisture content of solids are practical decision (design) parameters for system optimisation. The objective for the optimal control of batch granulation processes is to maximize the mass of product-sized particles with minimum time and binder consumption. The objective for the optimal control of the continuous process is to drive the process from one steady state to another in a minimum time with minimum binder consumption, which is also known as the state-driving problem. It has been known for some time that the binder spray-rate is the most effective control (manipulative) variable. Although other possible manipulative variables, such as feed flow-rate and additional powder flow-rate have been investigated in the complete research project, only the single input problem with the binder spray rate as the manipulative variable is addressed in the paper to demonstrate the methodology. It can be shown from simulation results that the proposed models are suitable for control and optimisation studies, and the optimisation algorithms connected with either steady state or dynamic models are successful for the determination of optimal operational conditions and dynamic trajectories with good convergence properties. 相似文献
88.
本文综述了国外碳纤维、陶瓷、聚芳酰胺、超高分子量聚乙烯、液晶聚合物纤维的发展现状,包括它们的生产能力、消费情况、性能特点,主要生产国和生产公司、产品牌号以及应用领域等,并指出了其生产进展和发展动向。 相似文献
89.
单片机系统的动态加密技术 总被引:2,自引:0,他引:2
单片机系统产品的加密和解密技术永远是一个矛盾的统一体。然而 ,为了更好的保护好自己的单片机技术成果和知识产权 ,加大解密成本 ,研究新型加密技术仍是保护成果的主要手段之一。文中在讨论了传统的单片机系统加密和解密技术的基础上 ,提出一种实用而有效的动态加密技术的实现方案。 相似文献
90.