Percolation theory approach to transport phenomena in porous media

The percolation theory approach to static and dynamic properties of the single- and two-phase fluid flow in porous media is described. Using percolation cluster scaling laws, one can obtain functional relations between the saturation fraction of a given phase and the capillary pressure, the relative permeability, and the dispersion coefficient, in drainage and imbibition processes. In addition, the scale dependency of the transport coefficient is shown to be an outcome of the fractal nature of pore space and of the random flow pattern of the fluids or contaminant.     

On the problem of axisymmetrically loaded shells of revolution with small elastic strains and arbitrarily large axial deflections

For the problem of axisymmetrically loaded shells of revolution with small elastic strains and arbitrarily large axial deflections, this paper suggests a group of state variable: radial displacement u, axial displacement w, angular, deflection of tangent in the meridian X, radial stress resultant H and meridional bending moment M_s, and derives a System of First-order Nonlinear Differential Equations under global coordinate system with these variables. The Principle of Minimum Potential Energy for the problem is obtained by means of weighted residual method, and its Generalized Variational Principle by means of identified Lagrange multiplier method.This paper also presents a Method of Variable-characteristic Nondimensionization with a scale of load parameter, which may efficientlky raise the probability of success for nonlinearity calculation. The obtained Nondimensional System of Differential Equations and Nondimensional Principle of Minimum Potential Energy could be taken as the theoretical basis for the numerical computation of axisymmetrical shells with arbitrarily large deflections.     

A STABILITY STUDY OF NAVIER-STOKES EQUATIONS (Ⅲ)

ＡＳＴＡＢＩＬＩＴＹＳＴＵＤＹＯＦＮＡＶＩＥＲ－ＳＴＯＫＥＳＥＱＵＡＴＩＯＮＳ（Ⅲ）ＳｈｉＷｅｉ－ｈｕｉ（施惟慧）（ｓｈａｎｇｈａｉＵｎｉｖｅｒｓｉｌｙ．Ｓｈａｎｇｈａｉ）（ＲｅｃｅｉｖｅｄＪａｎ．２０．１９９４；ＣｏｍｍｕｎｉｃａｔｅｄｂｙＣｈｉｅ...     

A stability study of Navier-Stokes equations (III)

In this paper, the necessary conditions of the existence of C² solutions in some initial problems of Navier-Stokes equations are given, and examples of instability of initial value (at t=0) problems are also given. The initial value problem of Navier-Stokes equation is one of the most fundamental problem for this equation various authors studies this problem and contributed a number of results. J. Lerav, a French professor, proved the existence of Navier-Stokes equation under certain defined initial and boundary value conditions. In this paper, with certain rigorously defined key concepts, based upon the basic theory of J. Hadamard partial differential equations¹, gives a fundamental theory of instability of Navier-Stokes equations. Finally, many examples are given, proofs referring to Ref. [4].     

Caristi type hybrid fixed point theorems in menger probabilistic metric space

I.IntroductionandPreliminariesInl976,CaristiprovedtheCaristi'sfixedpointtheoreminIll.Becausethistheoremdoesnotrequirethecontinuityofthemapping.ittindsapplicationsinmanyfields.Inl99l,S.S.Changetal.l'l,broughtforwardCaristi'sfixedpointtheoremandEkeland'svar…     

飞机－道面－土基动力耦合系统有限元分析

本文将飞机－道面－土基作为一个相互作用的动力系统，对飞机滑行情况下，弹性半空间地基上刚性道面板的动响应，采用有限元法进行了计算分析。结果表明，本文计算结果与现场实测值吻合很好。由于考虑了飞机和道面之间的耦合作用，避免了实测飞机对道面作用荷载的繁琐工作，因此本文方法具有明显的实用意义。     

空间杆系与叠层板组合结构的非线性稳定分析

本文用非线性有限元法研究一种空间杆系与复合材料叠层板组合结构的非线性稳定问题。将杆系离散成空间梁柱单元，将复合材料叠层板离散成复合材料叠层板单元，并考虑了几何非线性和板的成层正交各向异性性质。为了获得较高的计算效率并顺利通过稳定临界点，求解非线性平衡方程采用了变增量步长和柱面弧长法迭代策略。在考证了程序的正确性之后，具体分析了几个工程模型，得出了于工程设计有益的结论。     

底层大空间高层结构自由振动的实用计算方法

本文以连杆节间为界，按弹性支座上和Ｔｉｍｏｓｈｅｎｋｏ悬臂梁建立力墙部分的振动方程，按一般框架建立框架部分的振动方程，根据力，变形协调条件，形成底层大空间高层建筑结构的自由振动，并据此计算其自由振动。     

A new equilibrium existence theorem of generalized game

ＡＮＥＷＥＱＵＩＬＩＢＲＩＵＭＥＸＩＳＴＥＮＣＥＴＨＥＯＲＥＭＯＦＧＥＮＥＲＡＬＩＺＥＤＧＡＭＥＤｉｎｇＸｉｅ－ｐｉｎｇ（丁协平）（ＳｉｃｈｕａｎＮｏｒｍａｌＵｎｉｖｅｒｓｉｔｙ,Ｃｈｅｎｇｄｕ）ＡＮＥＷＥＱＵＩＬＩＢＲＩＵＭＥＸＩＳＴＥＮＣＥＴＨＥ...     

侧柱对串列双柱脉动压力的干扰

研究了串列双圆柱旁加上一个等直径的圆柱，组成一个等边三角形排列的三圆柱的脉动压力分布．着重研究侧柱对串列双圆柱脉动压力分布的影响．研究的结果表明，绕流等边三角形排列的三圆柱，受影响最严重的是后柱．脉动压力分布出现了严重的不对称，外侧的压力脉动极其强烈，内侧的压力脉动较弱，与时均压力分布，很好的对应关系．另外，侧柱对于串列双圆柱是否达到超过临界间距的绕流流态，有很大的影响