关于热传导－对流问题的有限元方法分析

关于热传导－对流问题的有限元方法分析沈树民（苏州大学）ＴＨＥＦＩＮＩＴＥＥＬＥＭＥＮＴＡＮＡＬＹＳＥＳＦＯＲＴＨＥＣＯＮＤＵＣＴＩＯＮ－ＣＯＮＶＥＣＴＩＯＮＰＲＯＢＬＥＭＳ￥ＳｈｅｎＳｈｕ－ｍｉｎ（ＳｕｚｈｏｕＵｎｉｖｅｒｓｉｔｙ）Ａｂｓｔｒａｃｔ：...     

GLOBAL ATTRACTIVITY OF LINEAR NON－AUTONOMOUS NEUTRAL DIFFERENTIAL－DIFFERENCE EQUATIONS

ＧＬＯＢＡＬＡＴＴＲＡＣＴＩＶＩＴＹＯＦＬＩＮＥＡＲＮＯＮ－ＡＵＴＯＮＯＭＯＵＳＮＥＵＴＲＡＬＤＩＦＦＥＲＥＮＴＩＡＬ－ＤＩＦＦＥＲＥＮＣＥＥＱＵＡＴＩＯＮＳＨＥＸＵＥＺＨＯＮＧ（何学中）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍａｔｉｃｓ，Ｎｉｎｇｘｉ...     

非线性Sobolev方程的特征－差分方法

非线性Ｓｏｂｏｌｅｖ方程的特征－差分方法由同顺（南开大学）ＴＨＥＣＨＡＲＡＣＴＥＲＩＳＴＩＣＤＩＦＦＥＲＥＮＣＥＭＥＴＨＯＤＦＯＲＡＮＯＮＬＩＮＥＡＲＳＯＢＯＬＥＶＥＱＵＡＴＩＯＮ￥ＹｏｕＴｏｎｇ－ｓｈｕｎ（ＮａｎｋａｉＵｎｉｖｅｒｓｉｔｙ）Ａｂｓｔ...     

A SUFFICIENT CONDITION FOR NON－COEXISTENCE OF ONE DIMENSIONAL MULTICOLOR CONTACT PROCESSES

ＡＳＵＦＦＩＣＩＥＮＴＣＯＮＤＩＴＩＯＮＦＯＲＮＯＮ－ＣＯＥＸＩＳＴＥＮＣＥＯＦＯＮＥＤＩＭＥＮＳＩＯＮＡＬＭＵＬＴＩＣＯＬＯＲＣＯＮＴＡＣＴＰＲＯＣＥＳＳＥＳＬＩＵＸＩＵＦＡＮＧ（刘秀芳）ＷＡＮＧＪＵＮ（王军）（ＤｅｐａｒｔｍｅｎｔｏｆＭａｔｈｅｍ...     

GLOBAL STRUCTURE OF THE ORBITS OF A KIND OF N－DIMENSIONAL COMPETITIVE SYSTEMS

ＧＬＯＢＡＬＳＴＲＵＣＴＵＲＥＯＦＴＨＥＯＲＢＩＴＳＯＦＡＫＩＮＤＯＦＮ－ＤＩＭＥＮＳＩＯＮＡＬＣＯＭＰＥＴＩＴＩＶＥＳＹＳＴＥＭＳ￥ＣｈｅｎｇＣｈｕｎ－ｃｈｏｒ，Ｌｉｔｗｉｎ（郑振初）（ＨｏｎｇＫｏｎｇＩｎｓｔｉｔｕｔｅｏｆＥｄｕｃａｔｉｏｎ，香港...     

GLOBAL EXISTENCE FOR A PARTICULAR INHOMOGENEOUSCONVECTION DIFFUSION SYSTEM

ＧＬＯＢＡＬＥＸＩＳＴＥＮＣＥＦＯＲＡＰＡＲＴＩＣＵＬＡＲＩＮＨＯＭＯＧＥＮＥＯＵＳＣＯＮＶＥＣＴＩＯＮＤＩＦＦＵＳＩＯＮＳＹＳＴＥＭＺｈｕＣｈａｎｇｊｉａｎｇ（朱长江）ＺｈａｏＨｕｌｊｉａｎｇ（赵会江）（ＹｏｕｎｇＳｃｉｅｎｔｉｓｔＬａｂｏｒａｔｏ...     

GOPPA CODES FROMARTIN-SCHREIER FUNCTION FIELDS

ＧＯＰＰＡＣＯＤＥＳＦＲＯＭＡＲＴＩＮ－ＳＣＨＲＥＩＥＲＦＵＮＣＴＩＯＮＦＩＥＬＤＳ￥ＨＡＮＷＥＮＢＡＯ（ＤｅｐａｔｍｅｌｌｔｏｆＭａｔｈｅｍａｔｉｃｓ，ＳｉｃｈｕａｎＵｎｉｖｅｒｓｉｔｙｔＣｈｅｎｇｄｕ６１００６４，Ｓｉｃｈｕａｎ，Ｃｈｉｎａ．）Ａ...     

OPTIMAL MODELS FOR THE FIRST ARRIVAL TIME DISTRIBUTION FUNCTION IN CONTINUOUS TIME－WITH A SPECIAL CASE

ＯＰＴＩＭＡＬＭＯＤＥＬＳＦＯＲＴＨＥＦＩＲＳＴＡＲＲＩＶＡＬＴＩＭＥＤＩＳＴＲＩＢＵＴＩＯＮＦＵＮＣＴＩＯＮＩＮＣＯＮＴＩＮＵＯＵＳＴＩＭＥ－ＷＩＴＨＡＳＰＥＣＩＡＬＣＡＳＥＬＩＮＹＵＡＮＬＩＥ（林元烈）（ＤｅｐａｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＭａ...     

LARGE DEVIATIONS FOR INFINITE DIMENSIONAL AND REVERSIBLE REACTION－DIFFUSION PROCESSES

ＬＡＲＧＥＤＥＶＩＡＴＩＯＮＳＦＯＲＩＮＦＩＮＩＴＥＤＩＭＥＮＳＩＯＮＡＬＡＮＤＲＥＶＥＲＳＩＢＬＥＲＥＡＣＴＩＯＮ－ＤＩＦＦＵＳＩＯＮＰＲＯＣＥＳＳＥＳＣＨＥＮＪＩＮＷＥＮ（陈金文）（ＤｅｐｅｒｔｍｅｎｔｏｆＡｐｐｌｉｅｄＭａｔｈｅｍａｔｉｃｓ，Ｔ...     

ON ALMOST PERIODIC SOLUTIONS FOR A CLASS OF FUNCTIONAL DIFFERENTIAL EQUATIONS

ＯＮＡＬＭＯＳＴＰＥＲＩＯＤＩＣＳＯＬＵＴＩＯＮＳＦＯＲＡＣＬＡＳＳＯＦＦＵＮＣＴＩＯＮＡＬＤＩＦＦＥＲＥＮＴＩＡＬＥＱＵＡＴＩＯＮＳ￥ＷａｎｇＺｈｅｎ（王震）＆ＬｕｏＹｉ（骆毅）（ＡｎｈｕｉＵｎｉｖｅｒｓｉｔｙ）Ａｂｓｔｒａｃｔ：Ｔｈｉｓｐａｐｅｒ...     

非定常的热传导──对流问题的混合有限元法

1．引言设oCRZ是足够光滑的有界区域，考虑非定常的、无量纲化的，而且带有热传导的粘性不可压缩流体力学运动问题：问题（I）．求。＝（。1，。2），p，T满足；其中。是流体的速度向量，P为压力，T是温度，。＞0是运动粘性系数，入＞0是GroshoffM，j＝（0，1）是M维向量。x二hi，x。）·当温度T是常数时，问题（I）变为Navier－StokesIW题，而当！是常数时，问题（I）变为定常问题．到目前为止，对问题（I）的研究尚不多，只给出了一些计算方法（见11－4］等），对于有限元解的误差分析就更少．1994年，沈树民在问中首先对定常的问…     

二维Navier-Stokes方程同位有限体积法的稳定性改进

1 引言 考虑不可压缩粘性流体的二维Navier-Stokes方程,它由速度压力公式和连续性方程的耦合组成.     

Approximation of the incompressible convective Brinkman–Forchheimer equations

This paper studies the approximation of solutions for the incompressible convective Brinkman–Forchheimer (CBF) equations via the artificial compressibility method. We first introduce a family of perturbed compressible CBF equations that approximate the incompressible CBF equations. Then, we prove the existence and convergence of solutions for the compressible CBF equations to the solutions of the incompressible CBF equations.     

ON DISCRETE PROJECTION AND NUMERICAL BOUNDARY CONDITIONS FOR THE NUMERICAL SOLUTION OF THE UNSTEADY INCOMPRESSIBLE NAVIER-STOKES EQUATIONS

1. IntroductionLet us consider the unsteady incompressible Navier--Stokes equations (INSE)on a two--dimensional rectangular region fl with boundary 0fl. Here w = (u, v)" is tl1e velocityvector, p is the pressure, and f a known vector function of x) y, and…     

Finite element approximation for equations of magnetohydrodynamics

We consider the equations of stationary incompressible magnetohydrodynamics posed in three dimensions, and treat the full coupled system of equations with inhomogeneous boundary conditions. We prove the existence of solutions without any conditions on the data. Also we discuss a finite element discretization and prove the existence of a discrete solution, again without any conditions on the data. Finally, we derive error estimates for the nonlinear case.

     

New explicit approximate solution of MHD viscoelastic boundary layer flow over stretching sheet

In this paper, the study the momentum and heat transfer characteristics in an incompressible electrically conducting non‐Newtonian boundary layer flow of a viscoelastic fluid over a stretching sheet. The partial differential equations governing the flow and heat transfer characteristics are converted into highly nonlinear coupled ordinary differential equations by similarity transformations. The resultant coupled highly nonlinear ordinary differential equations are solved by means of, homotopy analysis method (HAM) for constructing an approximate solution of heat transfer in magnetohydrodynamic (MHD) viscoelastic boundary layer flow over a stretching sheet with non‐uniform heat source. The proposed method is a strong and easy to use analytic tool for nonlinear problems and does not need small parameters in the equations. The HAM solutions contain an auxiry parameter, which provides a convenient way of controlling the convergence region of series solutions. The results obtained here reveal that the proposed method is very effective and simple for solving nonlinear evolution equations. The method is straightforward and concise, and it can also be applied to other nonlinear evolution equations in physics. Copyright © 2012 John Wiley & Sons, Ltd.     

Sobolev方程的CN全离散化有限元格式

首先给出Sobolev方程关于时间二阶精度的Crank-Nicolson(CN)时间半离散格式,然后直接从时间二阶精度的CN时间半离散格式出发,构造CN全离散化的有限元格式,并给出这种时间二阶精度的CN全离散化有限元解的误差估计.本文研究方法使得理论证明变得更简便, 也是处理Sobolev方程的一种新的尝试.     

MULTISTEP FINITE VOLUME APPROXIMATIONS TO THE TRANSIENT BEHAVIOR OF A SEMICONDUCTOR DEVICE ON GENERAL 2D OR 3D MESHES

In this paper, we consider a hydrodynamic model of the semiconductor device. The approximate solutions are obtained by a mixed finite volume method for the potential equation and multistep upwind finite volume methods for the concentration equations. Error estimates in some discrete norms are derived under some regularity assumptions on the exact solutions.     

Analysis of incompressible miscible displacement in porous media by characteristics collocation method

Miscible displacement of one incompressible fluid by another in a porous medium is modelled by a coupled system of two partial differential equations. The pressure equation is elliptic, whereas the concentration equation is parabolic but normally convection‐dominated. In this article, the collocation scheme is used to approximate the pressure equation and another characteristics collocation scheme to treat concentration equation. Existence and uniqueness of solutions of the algorithm are proved. Optimal order error estimate is demonstrated. © 2005 Wiley Periodicals, Inc. Numer Methods Partial Differential Eq, 2006     

A Lagrangian Scheme à la Brenier for the Incompressible Euler Equations

We approximate the regular solutions of the incompressible Euler equations by the solution of ODEs on finite-dimensional spaces. Our approach combines Arnold’s interpretation of the solution of the Euler equations for incompressible and inviscid fluids as geodesics in the space of measure-preserving diffeomorphisms, and an extrinsic approximation of the equations of geodesics due to Brenier. Using recently developed semi-discrete optimal transport solvers, this approach yields a numerical scheme which is able to handle problems of realistic size in 2D. Our purpose in this article is to establish the convergence of this scheme towards regular solutions of the incompressible Euler equations, and to provide numerical experiments on a few simple test cases in 2D.