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601.
The steady axisymmetric flow of an incompressible fluid into a vertical well hydrodynamically perfectly drilled into a stratified inhomogeneous half-space consisting of three layers with different permeabilities is considered. The boundaries of the layers are assumed to be horizontal planes and the roof of the upper layer is assumed to be impermeable. The flow obeys a linear Darcy’s law. The pressure distribution on the well is assumed to be given, which is the main obstacle to finding an exact solution of the problem. Beginning with the classical studies of Muskat and Charnyi [1, 2], approximate solutions of such problems have been constructed as a superposition of flows generated by point sources with given intensities, distributed along the well axis in accordance with a fairly simple law. In the present study, this approach is used to obtain an integral equation for the source density distribution, which is then solved numerically. Comparison with the known exact solution for a thin elongated ellipsoid (“needle”) shows that this approach makes it possible to ensure an accuracy which at any rate is sufficient for applications. 相似文献
602.
I. Yu. Tsvelodub 《Journal of Applied Mechanics and Technical Physics》2007,48(5):708-711
An elastic plate with a physically nonlinear inclusion of an arbitrary shape is considered. This plate is subjected to pure
bending under the action of transverse forces and bending moments applied at the external boundary of the plate. There are
no loads distributed over the surface. The problem of finding external actions that provide a necessary uniform moment state
in the inclusion, i.e., prescribed constant moments and curvatures, is formulated and solved.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 48, No. 5, pp. 104–107, September–October, 2007. 相似文献
603.
饱和黏弹性多孔介质中的平面波及能量耗散 总被引:4,自引:0,他引:4
研究了流体饱和不可压黏弹性多孔介质中的非均匀平面波及其能量流和能量耗散规律. 在流
相和固相物质微观不可压、固相骨架宏观服从积分型本构关系和小变形的假定下,利用
Helmholtz分解,得到了饱和黏弹性多孔介质中非均匀平面波的一般解以及纵波、横波相速
度和衰减率等的解析表达式,分析了平面波传播矢量和衰减矢量之间的关系. 数值结果表明
孔隙流体与固相骨架间的相互作用以及固相骨架的黏性对波的相速度、衰减率等有着显著的
影响. 同时,得到了饱和黏弹性多孔介质的能量方程,给出了能量流矢量和能量耗散率. 对
非均匀平面纵波和横波,推导了平均能量流矢量和平均能量耗散率的解析表达式. 相似文献
604.
多晶体变形、应力的不均匀性及宏观响应 总被引:9,自引:0,他引:9
从单晶滑移变形分析的角度探讨多晶体塑性变形和应力的不均匀性及宏观力学响应:建议了
一种当前构形下以应力为基本变量的单晶黏塑性增量迭代计算方法;用Voronoi晶粒集合体
模型研究多晶体由于晶粒几何及取向的随机性造成的变形和应力的不均匀性, 进行了多晶集
合体的宏观响应和晶粒位向演化数值分析. 结果表明:(1)多晶体内等效塑性应变和应力分量在统计上呈现高斯分布,在应变硬化过程中, 随着塑性变形增加多晶体微观应力的统计变异系数会越来越大;(2)用Voronoi模型计算可得到沿最大剪应力方向的滑移变形带;(3)多晶体内最高三轴拉应力一般出现在晶界特别是三晶交界处;(4)Voronoi模型能用于织构分析. 相似文献
605.
The results of a numerical investigation of the process of oil displacement in a stratified inhomogeneous formation on the basis of the two-phase flow model with account for capillary forces are presented. It is shown that in many cases the vertical inhomogeneity of oil reservoirs may not be a cause of nonuniform displacement and the non-recovery of large oil reserves by the time of water breakthrough to the extraction surface. The action of the capillary forces is an additional factor leading to equalization of the water propagation front in the inhomogeneous formation, water breakthrough delay, and intensification of the mass transfer between the layers with different permeabilities. Analysis of the contribution of the interlayer flows to the water flooding of low-permeability formation intervals calls into question the practicability of blocking high-permeability inclusions in the neighborhood of pumping wells. 相似文献
606.
计算特征向量摄动量的混合基展开法 总被引:1,自引:0,他引:1
在结构修改和模型校正中,模态展开法是计算特征向量摄动量的常用方法之一,但当高阶模态被截断时,它会带来很大的截断误差。本文利用已知的有限阶模态,构造了N维欧氏空间的一个新基-混合基,并将特征向量的摄动量在新基上展开来计算特征向量的一、二阶 摄动量。该方法使得不管截模态个数的多少,其精度总与全模态展开法相同,且计算量都远少于全模记展开法;与改进的部分民开法相比,本方法不要求所截留的模态边连续的低阶模态 相似文献
607.
608.
A method of interface inversion in inhomogeneous media 总被引:1,自引:0,他引:1
First, an approximate solution of time domain interface scattering field is derived by extending the classical Born approximation
in the problem of interface scattering. In accordance with the solution form, a projection density compensation (PDC) inversion
method is developed according to the projection slice theorem, which is valid for the cases of inhomogeneous media and wave
mode transformation. Finally, in the model of layered media, the calculation algorithm and the simulation inversion comparison
results of point defect, crack, and crack on an interface, as well as the experiment method and results in the condition of
acoustic wave, are given.
The project supported by the National Natural Science Foundation of China (No.19232031) and Chinese Education Commission Science
Foundation 相似文献
609.
A. O. Vatul’yan M. A. Dvoskin P. S. Satunovskii 《Journal of Applied Mechanics and Technical Physics》2006,47(3):439-445
A method is proposed to analyze wave fields in an elastic layer with elastic properties varying arbitrarily with depth. The
method is based on reducing the boundary-value problem to a system of Fredholm integral equations of the second kind, which
is then analyzed numerically. Some features of the structure of dispersion sets are analyzed and, in particular, their asymptotes
are constructed.
__________
Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 47, No. 3, pp. 157–164, May–June, 2006. 相似文献
610.
J.S. He Y.S. Tao K. Porsezian A.S. Fokas 《Journal of Nonlinear Mathematical Physics》2013,20(3):407-419
We consider an inhomogeneous Hirota equation with variable dispersion and nonlinearity. We introduce a novel transformation which maps this equation to a constant coefficient Hirota equation. By employing this transformation we construct the rogue wave solution of the inhomogeneous Hirota equation. Furthermore, we demonstrate that one can control the rogue wave dynamics by suitably choosing the dispersion and the nonlinearity. These results suggest an efficient approach for controlling the basic features of the relevant rogue wave and may have practical implications for the management of the rogue waves in nonlinear optical systems. 相似文献