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51.
油,水二相流固耦合渗流的数学模型 总被引:12,自引:1,他引:11
为了正确模拟油藏中流体流动的动态过程,必须考虑由于注水和开采而引起的多相流体的流动、应力状态的变化和储集层变形之间复杂的相互作用。但由于这种问题的控制方程是三维非线性耦合方程,因此,很难模拟这种耦合作用。利用广义的Biot理论建立了一个完全耦合的数学模型,它描述可变形油藏中岩石变形和油水流动的这种相互作用。模型中假设岩石骨架具有弹塑性特性,流体是可压缩的。以岩石骨架位移和油水压力为未知变量所建立的控制方程,包括岩石骨架的平衡方程和流体(油、水)的连续性方程。所建立的流固耦合模型在石油工程,特别是在油藏数值模拟中有广泛的应用。参8(陈志宏摘 相似文献
52.
It is shown that the decomposition of a mixture of nitrates or coprecipitated carbonates or hydroxides of Mg and Nd form catalysts manifesting similar catalytic properties, while the catalyst obtained by impregnation is more active but much less selective. The mechanism of formation of the catalytically active phase and the nature of the active sites are discussed. 相似文献
53.
本文对四维空间直线绕平面旋转的轨迹进行一投详尽的讨论,按照直线与“轴平面”的相对位置不同,该旋转轨迹分别为圆柱面、圆锥面和单叶回转双曲面,并认为这些回转曲面的轴线是过该直线的与“轴平面”垂直的超平面与“轴平面”的交线。 相似文献
54.
煤气鼓风机为适应系统煤气量的变化采用改变风机的转速来进行调节是一有效的节能方法。本文介绍了液力偶合器的结构特点、工作原理及其在煤气鼓风机系统中的应用,以实现风机的调速,并取得了明显的节能效果。 相似文献
55.
56.
A. M. Chandler 《Engineering Structures》1992,14(6):354-360
The results of a parametric study of torsional coupling effects in the response of asymmetric buildings to a grouped selection of 45 strong motion earthquakes from Europe, North America, the Middle East and Southern Pacific are presented. The period dependency of the key response parameters is studied in relation to the site dependent criteria employed by certain earthquake-resistant design codes for specifying the lateral shear forces to be resisted by the structural frames and/or walls. Unlike lateral forces, the torsional response is relatively insensitive to the ration of peak ground accelaration to velocity, which has been used in previous studies as a measure of the effect on earthquake ground motions of site soil conditions and epicentral distance. The results show that the effect of torsional coupling on edge displacement response is more pronounced in stiff, short period structures. However, the dynamic shear and torque responses are relatively insensitive to variations in structural period. Codified design provisions for torsional effects specified in the United States, Canadian and European seismic building regulations are assessed, along with alternative proposals, in relation to the analytical results. It is concluded that in some cases special provisions are needed for short period asymmetric systems, a feature which has been neglected by the codes and inadequately accounted for in previous proposals. 相似文献
57.
下拉菜单作为应用软件系统的用户界面已成为一种趋势。本文提供一种可以在UNIX和DOS操作系统环境下运行的通用菜单系统UMS(Universal Menu System)。文中对UMS中菜单的数据结构、菜单的用户描述、菜单系统程序的自动生成、菜单的初始化、菜单的实现技术和操作以及应用软件的耦合等技术问题都进行了详细的讨论。同时也指出了软件存在的问题。 相似文献
58.
Electric dipoles radiate an electromagnetic field into their surroundings. The electric and magnetic fields from a point source or from linear dipoles have components parallel to a spherical surface but also a radial component. In most investigations on radiated fields, only the part of the electric field that is parallel to a spherical surface is taken into account. The argument is that only that component contributes to the radiated energy. Here we show that the phase front in the lower half space is not a spherical surface and hence, the radial components contribute to radiated energy. We show differences in radiation patterns for point electric dipoles and linear dipoles, either modeled as perfectly conducting wires or as resistively loaded wires. Our primary interest lies with improving image resolution through processing of Ground-Penetrating Radar data. Here the emphasis lies with understanding the radiation characteristics of linear dipoles that can be incorporated with image processing algorithms. The model uses a thin-wire approximation for the transmitter antenna. The solution to the discrete system of equations is solved, incorporating interaction between the interface, using a CGFFT scheme including symmetrization and a newly developed preconditioning operator. We look at the electric and magnetic fields as well as the time-averaged Poynting vector radiation patterns in the E-plane and H-plane of the transmitting antenna. The results show that the radial component of the radiated electric and magnetic field is not negligible, even at distances more than seven wavelengths away from the antennas. 相似文献
60.
A compact lumped‐element equivalent circuit model of two‐layer integrated spiral inductors on silicon substrates is developed in this article. Based on this proposed model, excellent agreements are achieved between the measured and simulated S‐parameters for different inductors. Also, both self‐ and mutual inductances of two‐layer inductors are accurately extracted, and their overall performances are understood clearly. © 2003 Wiley Periodicals, Inc. Int J RF and Microwave CAE 13: 148–153, 2003. 相似文献