首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 93 毫秒
1.
建立了描述具有几何和物理非线性均匀柱动力学行为的偏微分-积分方程,柱的材料满足Leadder-man非线性本构关系,对两端简支的情形,采用Galerkin方法简化为常微分一积分方程;然后通过引进附加变量的方法进一步简化为常微分方程。  相似文献   

2.
The integro-partial-differential equation that governs the dynamical behavior of homogeneous viscoelastic beams with geometric and material nonlinearities is established. The material of the beams obeys the Leaderman nonlinear constitutive relation. In the case of simple supported ends, the Galerkin method is applied to simplify the integro-partial-differential equation to a integro -differential equation. The equation is further simplified to a set of ordinary differential equations by introducing an additional variable. Finally, the numerical method is applied to investigate the dynamical behavior of the beam, and results show that chaos occurs in the motion of the beam.  相似文献   

3.
l introductionThe Galerkin trUncation is widely used to stody thedynandcal behavior (especially the nonlinear dynamicalbehavior) of,trU.tUre,[i]. The Galerkin method is alsoaPPlied to stUdy dynamical behavior of viscoelashcbeams. Suire and Cederbaum [2] analyzed periodic andchaohc behavior of viscoelastic beams with the Idledeflection, and the constitUtive relation in their work isthe BoltZmann superposition Principle. Argyris[']myes-tigated chaohc motion of viscoelastic beamsbased on a …  相似文献   

4.
考虑剪切效应有限变形粘弹性板的动力稳定性   总被引:4,自引:0,他引:4  
Based on Reddy‘s theory of plates with higher-order shear deformations and the Boltzmann superposition principles,the governing equations were established for dynamic stability of viscoelastic plates with finite deformations taking account of shear effects,The Galerkin method was applied to simplify the set of equations.The numerical methods in nonlinear dynamics were used to solve the simplified system.It could e seen that there are plenty of dynamic properties for this kind of viscoelastic plates under transverse harmonic loads.The influences of the transverse shear deformations and material parameter on the dynamic behavior of nonlinear viscoelatic plates were investigated.  相似文献   

5.
介绍一种求解非线性偏微分方程行波解的方法,运用这种方法获得mkdv方程的行波解.在求解方程的过程中,引入一个变元u(x,t)=u(ξ)=u[k(x-ωt)]并代入方程,进行简单的求偏导数运算,将难以解决的非线性偏微分方程化为易于求解的代数方程,最后得到方程的行波解.这种方法还可推广到高维非线性演化方程求解.  相似文献   

6.
Based on convolution-type constitutive equations for linear viscoelastic materials with damage and the hypotheses of Timoshenko beams with large deflections, the nonlinear equations governing dynamical behavior of Timoshenko beams with damage on viscoelastic foundation were firstly derived. By using the Galerkin method in spatial domain, the nonlinear integro-partial differential equations were transformed into a set of integro-ordinary differential equations. The numerical methods in nonlinear dynamical systems, such as the phase-trajectory diagram, Poincare section and bifurcation figure, were used to solve the simplified systems of equations. It could be seen that simplified dynamical systems possess the plenty of nonlinear dynamical properties. The influence of load and material parameters on the dynamic behavior of nonlinear system were investigated in detail.  相似文献   

7.
Based on convolution-type constitutive equations for linear viscoelastic materials with damage and the hypotheses of Timoshenko beams with large deflections, the nonlinear equations governing dynamical behavior of Timoshenko beams with damage on viscoelastic foundation were firstly derived. By using the Galerkin method in spatial domain, the nonlinear integro-partial differential equations were transformed into a set of integro-ordinary differential equations. The numerical methods in nonlinear dynamical systems, such as the phase-trajectory diagram, Poincare section and bifurcation figure, were used to solve the simplified systems of equations. It could be seen that simplified dynamical systems possess the plenty of nonlinear dynamical properties. The influence of load and material parameters on the dynamic behavior of nonlinear system were investigated in detail.  相似文献   

8.
利用速探函数法,应用到KdV方程和Burgers方程和KdV—Burgers方程化为一个易于求解的代数方程,然后用待定系数法确定相应的常数,可简洁求得一类非线性偏微分方程的精确新解,此方法可望进一步推广用于求解其他非线性偏微分方程。  相似文献   

9.
利用增算子不动点定理讨论一阶抽象Volterra型脉冲微分积分方程周期边值问题的广义解,并建立了迭代公式。  相似文献   

10.
利用一个新的比较结果和Moench不动点定理,研究了Banach空间非线性混合型微分-积分方程初值问题整体解的存在性,作为应用,得到了两类三阶方程混合边值问题的整体解。  相似文献   

11.
In this paper, a nonlinear mathematical model for analyzing dynamical response to the large deformation of piles with initial displacements is firstly established with the arc-coordinate, and it is a set of nonlinear integral-differential equations, in which, the Winkeler model is used to simulate the resistance of the soil to the pile. Secondly, a set of new auxiliary functions are introduced. The differential-integral equations are transformed into a set of nonlinear differential equations,and the differential quadrature method (DQM) and the finite difference method (FDM) are applied to discretize the set of nonlinear equations in the spatial and time domains, respectively. Then, the Newton-Raphson method is used to solve the set of discretization algebraic equations at each time step. Finally, numerical examples are presented, and the dynamical responses to the deformation of piles, including configuration, bending moment and shear force, are graphically illuminated. In calculation, two types of initial displacements and dynamical loads are applied, and the effects of parameters on the dynamical responses of piles are analyzed in detail.  相似文献   

12.
13.
INTRODUCTIONInrecentyears,orthogonalpolynomialsandfunctionsdevelopedbyChangetal.( 1 986)havebeensuccessfullyappliedinthefieldofdynamicsystems,foranalysisandidentificationoflinearsystemsandtheoptimalcontrol (Tsayetal.,1 987) .Themainadvantageofthistechniqueisthe…  相似文献   

14.
利用非线性演化方程精确行波解的手工推导和计算的原理,结合计算机符号计算,在计算机代数系统Maple上,开发基于非线性代数方程组吴文俊消元法的非线性演化方程精确行波解的自动求解软件包,实现了非线性方程(组)的求解过程的完全自动化.  相似文献   

15.
The simulation of a high-temperature gas-cooled reactor pebble-bed module (HTR-PM) plant is discussed. This lumped parameter model has the form of a set differential algebraic equations (DAEs) that include stiff equations to model point neutron kinetics. The nested approach is the most common method to solve DAE, but this approach is very expensive and time-consuming due to inner iterations. This paper deals with an alternative approach in which a simultaneous solution method is used. The DAEs are discretized over a time horizon using collocation on finite elements, and Radau collocation points are applied. The resulting nonlinear algebraic equations can be solved by existing solvers. The discrete algorithm is discussed in detail; both accuracy and stability issues are considered. Finally, the simulation results are presented to validate the efficiency and accuracy of the simultaneous approach that takes much less time than the nested one.  相似文献   

16.
基于麦克斯威尔方程,给出导电薄板的非线性磁弹性振动方程,以及磁场环境下的电动力学方程和电磁力表达式。在此基础上,应用伽辽金法导出相应的非线性振动微分方程组,研究横向恒定磁场中周期载荷作用下梁式薄板的稳定性问题。根据李雅普诺夫近似稳定性理论,对稳态解的稳定性进行分析,得到稳定性的判定条件。通过对算例特征值的求解对振动的稳定性进行分析。  相似文献   

17.
有限差分方法就是一种数值解法,在一维输运方程定解中可以巧用它来解题,把表示变量连续变化关系的偏微分方程离散为有限个代数方程,然后利用电子计算机求此线性代数方程组的解。  相似文献   

18.
本文讨论一类积分微分方程组边值问题的奇摄动,应用微分不等式理论证明了解的存在并估计了余项。  相似文献   

19.
李晶 《唐山学院学报》2016,29(6):1-5,40
给出了横向磁场作用下矩形薄板的磁弹性振动方程,针对一边固定、三边简支的矩形薄板,通过位移模态展开,并利用Galerkin法得到两自由度内共振非线性振动微分方程组。算例分析中,利用数值方法得到了系统内共振时两阶模态的时间历程响应图和相平面图,并分别讨论了系统初值及磁场强度对系统振动的影响。结果表明,系统呈现明显的非线性内共振特征。  相似文献   

20.
本文利用Leray-Schauder理论及正反Lozenskii测度建立了非线性系统存在唯一的双曲周期解的代数判据.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号