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991.
苏铭德 《应用数学和力学(英文版)》1986,7(10):987-994
This paper presents finite element analysis of non-Newtonian fluid flow in 2-d branching channel. The Galerkin method and mixed finite element method are used. Here the fluid is considered as incompressible, non-Newtonian fluid with Oldyord differential-type constitutive equation. The non-linear algebraic equation system which is formulated with finite element method is solved by means of continuous differential method. The results show that finite element method is suitable for the analysis of non-Newtonian fluid flow with complex geometry. 相似文献
992.
In the present study, an effective model is proposed to predict the effective elastic behavior of the three-phase composite containing spherical inclusions, each of which is surrounded by an interphase layer. The constitutive equations are derived for the stress and strain of each phase of the composite subjected to a far-field tension. Based on these constitutive laws, the effective bulk, shear and Young’s modulus are obtained. A statistical debonding criterion is adopted to characterize the varying probability of the evolution of interphase debonding. Influences of debonding damage, particle volume fraction, interphase properties and bonding strength on overall mechanical behavior of composites are also discussed. Numerical analyses are carried out on particle-reinforced composites and the predictions have a good agreement with the experimental results. 相似文献
993.
本文给出了两对边简支另两对边任意支承的中间有任意多个单向弹性线支矩形板横向振动的一个新的解析解法、将弹性线支反力看作是作用于板上的待求外力,求得了含有来知的弹性线支反力的两对边简支矩形板的运动方程的解析解;利用弹性线支反力与板横向位移之间的线性关系导出频率方程;频率方程及振型函数的表述均与已有方法不同. 相似文献
994.
单侧界面条件下弹性波传播规律的研究 总被引:3,自引:1,他引:2
界面是介质间的分界面,把界面看成是双侧的,只是真实界面模型表述的一个极端,在很多情况下,它的另一个极端,即单侧界面模型可能更近于实际.在单侧界面条件下弹性波的传播问题,与双侧界面问题相比,还是一个尚未充分研究的领域.本文意在对这一领域的研究现状及问题作一评述和展望 相似文献
995.
继文[1],本文详细讨论了一个实例,对二阶弹性材料在Z方向的位移和应力作了数值计算,我们发现,二阶效应使Z方向位移减小而使应力trz的值在荷载作用圆内减小而在圆外却增加。 相似文献
996.
I.IntroductionBecauseofthenonlinearityoflargedeflectionproblemofthinplates,itisquitedifficulttoobtainitsaccuratesolution.Thereforeanapproximatesolutiontoitobtainedbyanappropriatemethodisdesired.Thetechniquesocalledperturbation,beingabletogiveresultswithadequateprecision,isofaprevailingandeffectiveonetobegenerallyaccepted.W.Z.Chientl]succesfullyobtainedanapproximatesolutiontothelargedeflectionproblemofthincircularplatefie-curalaxisymmetricallybyperturbationtechnique.X.Z.Wangl'Jgainedthedispl… 相似文献
997.
998.
利用光的干涉测钢丝杨氏弹性模量的方法 总被引:8,自引:0,他引:8
通过测定空气劈尖的光的干涉条纹间距,确定钢丝的微小伸长量,根据测量结果计算钢丝的杨氏弹性模量。 相似文献
999.
张英世 《应用数学和力学(英文版)》2000,21(7):783-790
IntroductionVibrationsofsteppedthinrectangularplateshavebeenresearchedbymechanicalworkers.ErcoliandLauraanalyzedvibrationsoftwo_stepthinrectangularplates[1],ZhangYingshietalstudiedvibrationsofn_stepone_waythinrectangularplatesonWinkler’sfoundation[1],ofn… 相似文献
1000.
Methods are presented for obtaining exact analytical representations of supercoiled equilibrium configurations of impenetrable
elastic rods of circular cross-section that have been pretwisted and closed to form rings, and a discussion is given of applications
in the theory of the elastic rod model for DNA. When, as here, self-contact is taken into account, and the rod is assumed
to be inextensible, intrinsically straight, transversely isotropic, and homogeneous, the important parameters in the theory
are the excess link Δℒ (a measure of the amount the rod was twisted before its ends were joined), the ratio ω of the coefficients
of torsional and flexural rigidity, and the ratio d of cross-sectional diameter to the length of the axial curve C. Solutions of the equations of equilibrium are given for cases in which self-contact occurs at isolated points and along
intervals. Bifurcation diagrams are presented as graphs of Δℒ versus the writhe of C and are employed for analysis of the stability of equilibrium configurations. It is shown that, in addition to primary, secondary,
and tertiary branches that arise by successive bifurcations from the trivial branch made up of configurations for which the
axial curve is a circle, there are families of equilibrium configurations that are isolas in the sense that they are not connected
to bifurcation branches by paths of equilibrium configurations compatible with the assumed impenetrability of the rod. Each
of the isolas found to date is connected to a bifurcation branch by a path which, although made up of solutions of the governing
equations, contains regions on which the condition of impenetrability does not hold.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献