含微裂纹材料的损伤理论

本文从含微裂纹材料的变形能出发引出了裂纹的方位张量。在考虑裂纹受压闭合与滑动摩擦的基础上,给出了损伤张量、损伤应变及有效弹性常数。文中给出了损伤机构离散化的方法,并对方位密度给出了演化方程。最后给出一个单向拉压的应力应变关系例子,并揭示了裂纹扩展时的应力突跌现象。     

三轴转台框架间动力学耦合及解耦研究

本文对三轴转台框架间的动力学耦合问题进行了分析和计算，并给出了三轴转台动力学一般方程。针对某型号转台，给出了它的动力学方程。根据逆系统理论证明了转台模型的可解耦性，并给出了解耦后的线性模型方程。     

振荡流中圆柱受力测量研究

本文叙述了测量振荡流中圆柱受力大小和性质的方法和步骤。给出了测量结果,并首次给出这种力的频谱特性。     

开口正方形板的应力分析(一)

根据Muskhelishvili的方法,给出了借助于多项式将正方形孔保角映射到单位圆的边值问题的通解,并通过叠加原理给出了双连通域边值问题的解。做为例子给出了开口正方形板在剪力作用下的应力分布。     

强非线性系统的频闪法

本文给出了求强非线性系统周期解的频闪法,并给出了该方法的数学证明。     

用样条函数法分析旋转组合壳

本文采用不等距三次Ｂ样条函数对旋转壳在整体坐标下的位移进行插值，给出了周向插值所必需满足的周期性条件，采用罚单元法，给出了组合壳体在整体坐标下的协调关系，与惯用方法相比，这种方法简单明了直观性强，易于接受。文末给出了算例。     

一类混凝土力学参数的迭代多尺度有限元预测方法

根据多级配骨料混凝土特点,给出了一种迭代多尺度有限元方法预测其等效力学参数。本文首先介绍了多级配骨料混凝土的材料特点并给出了计算混凝土多尺度模型,然后基于多尺度方法介绍了计算混凝土力学参数的计算程序,最后针对小湾大坝中混凝土给出了算例说明了此种方法在预测混凝土等效力学参数的有效性。     

结构非概率可靠性指标的求解方法

在结构的非概率可靠性方法中,结构的可靠性是用非概率可靠性指标来度量的。本文研究了区间变量的一般运算规则,给出了非概率可靠性指标的三种求解方法：定义法、转换法和优化法。给出了定义法的具体描述和实现方法,并给出了转换法的一般求解步骤和一种可通用的区间优化算法的实现过程。三种方法的给出,基本上解决了结构可靠性分析中非概率可靠性指标的求解问题。实例计算表明所提方法是有效和可行的。     

空间拦截最优末端导引规律研究的新方法

给出了空间拦截控制的非线性微分方程，并在非线性控制系统引入了结构力学中的多重子结构法，从而求出了空间拦截非线性最优末端导引规律，同时给出了相应的数值仿真。     

李萨如图在捷联惯导系统圆锥误差估计中的应用

分析了激光陀螺捷联惯导系统产生圆锥运动的原因，给出了估计圆锥误差的一般方法，并在此基础上给出了一种简单、实用的方法-李萨如图法，后比前更加接近工程应用。最后给出了验证试验结果。     

A solution of transport in porous media with equilibrium and kinetic reactions

A solution is presented to verify numerical computer codes of reactive transport with both equilibrium and kinetic reactions. A synthetic model of A ↔ B ↔ C → chain reactions is proposed to describe operator-splitting numerical schemes used in numerical computer codes. A reaction matrix is derived for both the equilibrium and the first-order kinetic reactions and further decoupled as a diagonal matrix. Therefore, the partial differential equations (PDEs) coupled by the reaction matrix can be transformed into independent PDEs, for which closed-form solutions exist or can be derived. The solution derived in this study is compared with numerical results.     

A Numerical Verification of Nontrivial Solutions for the Heat Convection Problem

A computer assisted proof of the existence of nontrivial steady-state solutions for the two-dimensional Rayleigh-Bénard convection is described. The method is based on an infinite dimensional fixed-point theorem using a Newton-like operator. This paper also proposes a numerical verification algorithm which generates automatically on a computer a set including the exact nontrivial solution. All discussed numerical examples take into account of the effects of rounding errors in the floating point computations.     

施工期混凝土浇筑块的脆弹性徐变应力分析

本文将线性徐变理论和脆弹性破坏模型相结合,推导出计算混凝土浇筑块温度徐变应力的非线性有限元递推公式,并编制了计算机程序。最后以东江拱坝基础部分浇筑块为例进行了分析计算。     

A problem for diffusion with relaxation in polymers

A nonlinear problem for penetrant diffusion with relaxation in polymers is considered. A numerical approach to solving this type of problems is developed. The proposed numerical scheme based on a finite element domain approximation and a time difference method can be used for numerical simulation of the considered penetrant diffusion in 2-D and 3-D domains. A numerical procedure and a corresponding computer code are created and tested for some examples in 1-D and 2-D domains.     

轴对称高速碰撞问题的拉格朗日无结构网格有限体积法的并行计算

给出计算轴对称高速碰撞问题的拉格朗日无结构三角形网格有限体积法的并行格式，并给出以小巨型机ＡｌｉａｎｔＦＸ／４０为目标计算机的算例数值模拟结果和效率分析     

Heat loss calculation in thermal simulation

An appraisal is presented for four different methods that are usually incorporated in thermal simulators to estimate the rate of heat loss to surroundings. The methods are the analytical solution using a superposition theorem, the analytical solution using a numerical approximation to the convolution integral, the semi-analytical solution, and the numerical solution. This appraisal includes expressing the equations in a form that can be incorporated into a fully implicit simulator, computer programming complexity, and the computer CPU time and memory storage requirements. A steam flood problem is used for the comparison, and the gas recovery, oil recovery, and heat loss performances for a reservoir in one and two dimensions are presented. It is found that the numerical solution is sensitive to grid size in the overburden, the semi-analytical solution is the simplest to program but its prediction is the least accurate, the analytical solution is the most expensive, whereas the analytical-numerical solution combines both accuracy and acceptable storage requirements, and therefore, it is recommended for use in thermal simulation.     

Statistics of quasi-geostrophic point vortices

The statistics of quasi-geostrophic point vortices is investigated theoretically and numerically, in order to understand fundamental aspects of quasi-geostrophic turbulence. The numerical computations are performed using the fast special-purpose computer for molecular dynamics simulations, MDGRAPE-2/3. The most probable vortex distributions are determined based on the maximum entropy theory. The theoretical predictions agree well with the numerical results.     

Tomographic diagnostics of technical materials and biological tissues using electric current

A mathematical model for impedance computer tomography methods is considered. The continuum formulation of the main problem is studied. Resolving integral equations are derived. A solution algorithm based on the Bubnov—Galerkin method with linearization of nonlinear resolving equations is developed. A numerical example is given, and numerical results are analyzed. Some drawbacks of the model are considered together with methods for avoiding them.     

岩石弹塑性破裂过程的数值模拟研究

分析了对于非均质、非连续且材料参数分布具有分散性和随机性的岩体介质,采用传统有限元法解决其工程问题的局限性．阐述了用岩石力学性质的分布特性来描述岩石材料不均匀性,并用蒙特卡洛模拟方法,将符合Weibull分布规律的材料参数赋予岩体结构中的各个单元体,进而用计算机进行数值模拟的研究方法．应用了在Windows95环境下利用FORTRAN Power Station4．0平台开发的具有可视性的“岩石弹塑性破裂过程分析”软件——REPFPA软件,对典型的岩石试样和巷道模型的弹塑性破裂过程进行数值模拟研究,得到了有价值的实验结果．证明把材料参数随机赋值方法引入到岩土类材料的弹塑性破裂过程分析中去,并用计算机进行数值模拟是研究岩石弹塑性破裂过程的一种有效方法。