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101.
含初缺陷复合材料圆柱曲板的动力屈曲分析 总被引:1,自引:1,他引:1
基于修正的一阶剪切变形理论,利用Hamilton原理导出包含横向剪切变形和转动惯量的复合材料长圆柱曲板的非线性动力方程,通过将位移和载荷展开为Fourier级数,把非线性偏微分方程组转化为二阶常微分方程组,并可由四阶Runge-Kutta方法数值求解,通过算例,讨论了有关因素对迭层复合材料圆柱曲板动力屈曲的影响。 相似文献
102.
An investigation of meterial properties of non-homogeneous cylindrically orthotropic circular plates
It has been been reported that the reduced stiffness of non-homogeneous cylindricallyorthotrpic circular plate varing exponentially with radius r is obtained by using thebending theory of a simple beamThe aim of this paper is to verify the effect of radius on the materal properties According to the flat stress-strain relation the values of material properties Er Ea and vθr which are the functions of radius r are obtained.Compared with the experimentalvalues the analytical values of the material properties are in essential agreement withtem. 相似文献
103.
V. F. Sivak 《International Applied Mechanics》2004,40(12):1419-1421
The resonance synchronization of the vibrations of a system of shells is studied. It is established that the vibrations of isolated components excite the vibrations of the whole system, consisting of three cylindrical shells on a common elastic base.__________Translated from Prikladnaya Mekhanika, Vol. 40, No. 12, pp. 134–137, December 2004. 相似文献
104.
On Solutions of Some Non-Linear Differential Equations Arising in Newtonian and Non-Newtonian Fluids
Mohyuddin M. R. Hayat T. Mahomed F. M. Asghar S. Siddiqui A. M. 《Nonlinear dynamics》2004,35(3):229-248
Some steady as well as unsteady solutions of the equations of motion for an incompressible Newtonian and non-Newtonian (second-grade)
fluids are obtained by applying different methods including the Lie symmetry group method. The flows considered are axially
symmetric with the swirling motion, and the governing equations for second-grade fluid flow have been modeled. Expressions
for streamlines, velocity and vorticity components are constructed explicitly in each case. Exact analytical solutions in
second-grade fluid are obtained and compared with the corresponding viscous solutions. 相似文献
105.
The buckling problem for longitudinally corrugated cylindrical shells under external pressure is solved. The solution makes
practically exact allowance for the geometry and buckling modes of the shell. The inaccuracy of the results is due to the
assumption that the subcritical state is momentless. Shells consisting of cylindrical panels of smaller radius and noncircular
shells with sinusoidal corrugations are analyzed for stability. The practical applicability of such shells is demonstrated
__________
Translated from Prikladnaya Mekhanika, Vol. 43, No. 11, pp. 66–79, October 2007. 相似文献
106.
Landon M. Kanner 《International Journal of Non》2007,42(2):204-215
This paper is concerned with investigation of the effects of strain-stiffening on the classical limit point instability that is well-known to occur in the inflation of internally pressurized rubber-like spherical thin shells (balloons) and circular cylindrical thin tubes composed of incompressible isotropic non-linearly elastic materials. For a variety of specific strain-energy densities that give rise to strain-stiffening in the stress-stretch response, the inflation pressure versus stretch relations are given explicitly and the non-monotonic character of the inflation curves is examined. While such results are known for constitutive models that exhibit a gradual stiffening (e.g. exponential and power-law models), our primary focus is on materials that undergo severe strain-stiffening in the stress-stretch response. In particular, we consider two phenomenological constitutive models that reflect limiting chain extensibility at the molecular level. It is shown that for materials with sufficiently low extensibility no limit point instability occurs and so stable inflation is then predicted for such materials. Potential applications of the results to the biomechanics of soft tissues are indicated. 相似文献
107.
A method for solving problems of fracture of an infinite solid with a circular cylindrical cavity and a coaxial cylindrical crack near the surface under an uniform axial compression is proposed using a non-classical criterial approach associated with a mechanism of a local stability loss near the defect. The theory of integral Fourier transforms and series expansions are used to reduce these problems to a system of paired integral equations and then to a system of linear algebraic equations with respect to the contraction parameter. 相似文献
108.
On Free Nonlinear Vibrations of Fluid-Filled Cylindrical Shells with Multiple Natural Frequencies 总被引:1,自引:0,他引:1
Nonlinear free vibrations of a cylindrical shell fully filled with a perfect incompressible fluid are studied. The case is
examined where two natural frequencies of the shell are close
__________
Published in Prikladnaya Mekhanika, Vol. 41, No. 10, pp. 127–138, October 2005 相似文献
109.
110.
轴向瞬间阶梯载荷下圆柱壳动力屈曲的双特征参数分析 总被引:3,自引:0,他引:3
对于轴向瞬间阶梯载荷下圆柱壳的弹性非轴对称动力屈曲问题,将临界应力和屈曲惯性项指数参数作为双特征参数求解。由能量转换和守恒准则,导出压缩波阵面上的屈曲变形附加约束条件。失稳控制方程、边界条件和波阵面上的连续条件,连同此附加约束条件构成求解两个特征参数和动力失稳模态的完备定解条件。由伽辽金法得出求解双特征参数问题的数值方法。 相似文献