Perzyna粘塑性模型的参变量变分原理*

Perzyna模型是粘塑性本构关系的主要形式之一,本文给出该模型的参变量变分原理,该原理将原问题化为求解带约束条件的泛函极值,其约束条件就是由粘塑性本构关系推导出的系统状态方程,所讨论的问题其塑性流动不受Drucker假定的限制,文中给出原理的证明,并研究弹塑性蠕变问题.     

The theory of static decay in computational mechanics

In this paper,a new mathematical form,matrix,continued fraction(MCF)isintroduced to describe the decay of effects of an equilibrant system of forces acting on asphere of an elastic body.By this way,the famous Saint-Venant’s principle is proved oftenbut not always valid in computational mechanics.     

COMPLEX FUNDAMENTAL SOLUTIONS FOR SEMI-INFINITE PLANE AND INFINITE PLANE WITH HOLE UNDER VARIOUS BOUNDARY CONDITIONS

I.IntroductionBoundaryelementmethod(BEM)hasbeenwidelyusedforlinearandnonlinearanalysisofengineeringstructures.ThetriditionalboundaryelementdiscretizationforthecouplingproblemoftbullditliollandpipeinFig.IisshowninFig.2.ConlparcdwithFEM,BEMIlasmoreadvantages.Inthispaper,thegeneralmethodoffindingthecomplexfundamentalsolutions(CFSs)I'orsemi-illfiniteplanealldintllliteplanewithholeundervariousboundaryconditions(aCs)hasbeenestablishedbyLlsillgRiemann-Schwarzsymmetricprincipleandsuperpositio…     

碘和硫增感剂在卤化银颗粒表面的分布

碘在卤化银微晶中的含量和分布对感光度的影响引起乳剂配方设计者的广泛注意和重视.颗粒中的碘引起其内部结构和表面结构的改变,导致微晶颗粒表面化学及物理性质的改变,从而引起增感敏化斑的位置、分布以及随后潜影斑、灰雾斑的形成等一系列的变化并最终影响乳剂的感光性能.如果我们想有效地控制卤化银乳剂的感光度、灰雾、反差等一系列感光性能,必须调整卤化银乳剂颗粒的表面结构.     

The growth of the void in a hyperelastic rectangular plate under a uniaxial extension

In the present paper, the finite deformation and stress analysis for a hyperelastic rectangular plate with a center void under a uniaxial extension is studied. In order to consider the effect of the existence of the void on the deformation and stress of the plate, the problem is reduced to the deformation and stress analysis for a hyperelastic annular plate and its approximate solution is obtained from the minimum potential energy principle. The growth of the cavitation is also numerically computed and analysed.Project supported by the National Natural Science Foundation of China     

The optimal control variational principle and finite elements analysis for viscoplastic dynamics

This paper presents the optimal control variational principle for Perzyna model which is one of the main constitutive relation of viscoplasticity in dynamics. And it could also be transformed to solve the parametric quadratic programming problem. The FEM form of this problem and its implementation have also been discussed in the paper.     

弹性圆板在一侧受均载而四周固定的条件下不用Kirchhoff-Love假设的一级近似理论(Ⅰ)

根据一般形状的三维弹性板不用Kirchhoff-Love假设的近似理论[1],[2],作者导出了三维弹性圆板的广义变分泛函,从而得到了圆板四周固定和一侧受均布载荷下的一级近似理论的微分方程和有关边界条件,其解析解答留待另文处理.     

弹性力学中的哈密顿系统及其变分原理*

作为哈密顿力学逆问题,从弹性力学基本方程推导出弹性力学中一个新的哈密顿系统及其变分原理。     

Mixed compatible element and mixed hybrid incompatible element variational methods in dynamics of viscous barotropic fluids

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The application of the variational principle in the constrained control system

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