共查询到20条相似文献,搜索用时 704 毫秒
1.
2.
具有自由边界的二维渗流问题 总被引:2,自引:1,他引:1
渗流的自由边界问题是工程上很受关注的问题.现有的数值分析方法需事先估计边界形态,逐次逼近.本文采用“变分不等式”的模式,结合有限元方法研究有自由边界的渗流问题,在整个结构区域内作有限元剖分,避免了传统的有限元分析中估计自由边界、反复修正计算区域的迭代过程.本文方法为简单而快速地分析渗流自由边界问题提供了一条有效的途径. 相似文献
3.
三维自助式类渗流细胞自动机的临界值 总被引:1,自引:0,他引:1
本文研究三维自助式类渗流细胞自动机的临界值.得出临界值pc=0的一些充分条件和必要条件.当pc>0时,利用定向点渗流的临界值,给出了pc上、下界的显式估计. 相似文献
4.
5.
6.
7.
程爱杰 《高校应用数学学报(A辑)》1994,(4):383-390
多孔介质中渗流驱动问题数值方法的研究,对合理经济地开发油田,了解地下油水运动规律有一定意义,特征线法结合差分或有限元法解渗流问题,在理论和应用上获得了成功,但还有很多问题进一步研究,前人研究多是假定流体不可压或微可压,本文研究一类完全可压缩两相驱动问题,采用特征线法与有限元法相结合,构造并分析了全离散数值格式,基于周期性假设,证明了最优L^2模误差估计。 相似文献
8.
程爱杰 《高校应用数学学报(A辑)》1994,(4)
多孔介质中渗流驱动问题数值方法的研究,对合理经济地开发油田,了解地下油水运动规律有一定意义。特征线法结合差分或有限元法解渗流问题,在理论和应用上获得了成功3-5,但还有很多问题需进一步研究2.前人研究多是假定流体不可压或微可压,本文研究一类完全可压缩两相驱动问题。采用特征线法与有限元法相结合,构造并分析了全离散数值格式,基于周期性假设,证明了最优L2模误差估计。 相似文献
9.
对可压缩二相渗流驱动问题提出分数步长特征差分格式 ,利用变分形式、能量方法、粗细网格配套、双二次插值、差分算子乘积交替性、高阶差分算子的分解、先验估计的理论和技巧 ,得到最佳阶l2 误差估计 .该方法已成功应用到油资源评估和强化采油数值模拟的生产实际中 相似文献
10.
本文研究含无穷拉普拉斯算子的渗流问题.运用改进的Bernstein方法和光滑逼近,分别建立了该问题严格正粘性解和非负粘性解关于空间变量的李普希兹估计. 相似文献
11.
Yirang Yuan 《Numerical Methods for Partial Differential Equations》2012,28(1):353-368
For the transient behavior of a semiconductor device, the modified method of characteristics with mixed finite element domain decomposition procedures applicable to parallel arithmetic is put forward. The electric potential equation is described by the mixed finite element method, and the electric, hole concentration and heat conduction equations are treated by the modified method of characteristics finite element domain decomposition methods. Some techniques, such as calculus of variations, domain decomposition, characteristic method, energy method, negative norm estimate and prior estimates and techniques are employed. Optimal order estimates in L2 norm are derived for the error in the approximation solution. Thus the well‐known theoretical problem has been thoroughly and completely solved.© 2010 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq 28: 353–368 2012 相似文献
12.
A LOCKING-FREE ANISOTROPIC NONCONFORMING FINITE ELEMENT FOR PLANAR LINEAR ELASTICITY PROBLEM 总被引:2,自引:1,他引:1
The main aim of this article is to study the approximation of a locking-free anisotropic nonconforming finite element for the pure displacement boundary value prob-lem of planar linear elasticity. The optimal error estimates are obtained by using some novel approaches and techniques. The method proposed in this article is robust in the sense that the convergence estimates in the energy and L2-norms are independent of the Lame parameterλ. 相似文献
13.
《Journal of the Egyptian Mathematical Society》2014,22(3):489-495
This paper is concerned with using the E-Bayesian method for computing estimates of the unknown parameter and some survival time parameters e.g. reliability and hazard functions of Lomax distribution based on type-II censored data. These estimates are derived based on a conjugate prior for the parameter under the balanced squared error loss function. A comparison between the new method and the corresponding Bayes and maximum likelihood techniques is conducted using the Monte Carlo simulation. 相似文献
14.
Ioannis Toulopoulos 《Applicable analysis》2020,99(7):1153-1170
ABSTRACTIn this paper, a stabilized space-time finite element method for solving linear parabolic evolution problems is analyzed. The proposed method is developed on a base of a space-time variational setting, that helps on the simultaneous and unified discretization in space and in time by finite element techniques. Stabilization terms are constructed by means of classical bubble spaces. Stability of the discrete problem with respect to an associated mesh dependent norm is proved, and a priori discretization error estimates are presented. Numerical examples confirm the theoretical estimates. 相似文献
15.
This paper is concerned with using the E-Bayesian method [M. Han, Applied Mathematical Modeling (2009) 1915–1922] for computing estimates for the parameter and reliability function of the Burr type XII distribution based on type-2 censored samples. The estimates are obtained based on squared error and LINEX loss functions. A comparison between the new method and the corresponding Bayes and maximum likelihood techniques is made using the Monte Carlo simulation. 相似文献
16.
§1.引言 本文讨论定常Stokes问题的几种罚函数有限元方法.设Ω是R~n中的有界区域,且具有Lipschita连续的边界?Ω.令非f∈(L~2(Ω))~n,则定常Stokes方程的齐次Dirichlet边值问题可描述如下:求(u,p)∈(H_0~1(Ω))~n×L~2(Ω),满足 相似文献
17.
《数学物理学报(B辑英文版)》2015,(6)
A kind of second-order implicit fractional step characteristic finite difference method is presented in this paper for the numerically simulation coupled system of enhanced(chemical) oil production in porous media.Some techniques,such as the calculus of variations,energy analysis method,commutativity of the products of difference operators,decomposition of high-order difference operators and the theory of a priori estimates are introduced and an optimal order error estimates in l~2 norm is derived.This method has been applied successfully to the numerical simulation of enhanced oil production in actual oilfields,and the simulation results are quite interesting and satisfactory. 相似文献
18.
Yirang Yuan 《Numerical Methods for Partial Differential Equations》2006,22(3):661-679
In modern numerical simulation of prospecting and exploiting oil‐gas resources and in environmental science, it is necessary to consider numerical method of nonlinear convection‐dominated diffusion problems. This thesis, starting from actual conditions such as the three‐dimensional characteristics of large‐scale science‐engineering computation, puts forward a kind of characteristic finite element alternating direction method with moving meshes. Some techniques, such as calculus of variations, operator‐splitting, generalized L2 projection, energy method, negative norm estimate, the theory of prior estimates and techniques, are adopted. Optimal order estimates in L2 norm are derived to determine the errors in the approximate solution. Thus the important theoretical problem has been solved. © 2005 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2005 相似文献
19.
éva Komáromi 《Annals of Operations Research》2012,200(1):93-108
The key focus of the paper is the introduction of a new deterministic approach to outstanding claims reserving in general insurance. The goals are to present a class of entropy programming models for determining claims reserves estimates; to justify popular simple techniques like the chain ladder technique and the separation method; to establish close connection of entropy programming models with log-linear models, maximum likelihood estimates; and to suggest new methods in the entropy programming framework. 相似文献
20.
袁益让 《数学物理学报(A辑)》2009,29(4):858-872
对多层非线性渗流耦合系统提出适合并行计算的特征分数步差分格式, 利用变分形式、能量方法、粗细网格配套、分片双二次插值、差分算子乘积交换性、高阶差分算子的分解、先验估计的理论和技巧, 得到收敛性的最佳阶的l2误差估计. 该方法已成功的应用到多层油资源评估的生产实际中. 相似文献