共查询到20条相似文献,搜索用时 15 毫秒
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本文分析了各向同性封闭圆柱壳的非线性自由振动。文中采用经典的非线性弹性力学方法推导了圆柱壳的大振幅运动方程,这些方程的静态形式与冯·卡门的板理论方程具有同样的精度。文中讨论了四种基本振动模态,并且还以数学公式的形式给出了一般的最终结果,一些例子以曲线给出结果,并进行了比较。结果还表明线性振动可以作为非线性振动的一种特例。 相似文献
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A detailed study, on the static response of cross-ply laminated composite circular cylindrical shell of revolution and shell panel with various support conditions, has been made using Levy type of solution and the classical shell theories of FlSanders, Love and Donnell in an unified form. It has been shown that while developing a Levy type of solution using aforementioned theories, certain difficulty is encountered for determining the particular integral in respect of Fl Sanders and Love theories. This difficulty has been overcome by making use of the membrane solution as a particular integral. A comparative study has been carried out using the above shell theories for different geometrical parameters, lamination schemes and support conditions. It has been shown that Donnell theory predicts inaccurate results for certain lamination schemes, support conditions and geometrical parameters of the shell. It is suggested that, for developing shear deformation shell theories, it would be better to use a more accurate shell theory like Flügge Sommario. La risposta statica di gusci cilindrici circolari di materiale composito laminato, a strati incrociati, e di pannelli con varie condizioni di supporto viene analizzata utilizzando in una forma unificata soluzioni tipo Levy e le classiche teorie dei gusci di Flügge Sanders, Love e Donnell. Si mostra che nello sviluppare una soluzione di tipo Levy si incontra una certa difficoltà nel determinare l'integrale particolare rispetto alle teorie di Flügge, Sanders e Love. Tale difficoltà viene superata usando la soluzione di membrana come integrale particolare. Viene sviluppato uno studio comparativo facendo uso delle suddette teorie dei gusci per differenti parametri geometrici, schemi di laminazione e condizioni di vincolo. Si mostra che la teoria di Donnell fornisce risultati non accurati per certi schemi di laminazione, condizioni di supporto e parametri geometrici del guscio. Si suggerisce che per sviluppare teorie dei gusci che tengano conto delle deformazioni di scorrimento sarebbe più opportuno l'uso di una teoria dei gusci più accurata come ad esempio quella di Flügge. 相似文献
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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
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Published in Prikladnaya Mekhanika, Vol. 41, No. 10, pp. 127–138, October 2005 相似文献
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The paper reports on experimental results for a dynamic system of two identical shells filled with a liquid and placed on a common elastic foundation. It is established that vibrations excited in one of the shells synchronize the vibrations of the whole system 相似文献
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A technique is proposed to determine the natural frequencies of rib-reinforced cylindrical shells with low shear stiffness. The equations of motion based on the Timoshenko model are used. The influence of the transverse shear moduli of the shell and ribs on the minimum natural frequencies and corresponding modes is studied by way of numerical examples. It is shown that the effect of the discrete ribs is different from that predicted by the classical theory of ribbed shells__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 4, pp. 66–74, April 2005. 相似文献
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The paper addresses dynamic problems for discretely reinforced shells with initial deflections. Timoshenko theory is used. A numerical method of solving such problems is developed and theoretically justified. Numerical results for a specific problem are presented__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 1, pp. 60–68, January 2005. 相似文献
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E. K. Ankyanets 《International Applied Mechanics》2005,41(10):1177-1181
The vibrations of a cylindrical shell reinforced with circular ribs attached to it by means of discrete elastic elements are
studied. The problem is solved by the finite-element method. The shell and ribs are modeled by a plane four-node finite element,
which is a combination of a four-node plane stress element and a four-node flexural element. The effect of the stiffness of
the elastic elements on the natural frequencies and modes is examined
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Translated from Prikladnaya Mekhanika, Vol. 41, No. 10, pp. 108–113, October 2005. 相似文献
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The forced nonlinear vibrations of a thin cylindrical shell completely filled with a liquid are studied. A refined mathematical model is used. The model takes into account the nonlinear terms up to the fifth power of the generalized displacement of the shell. The Bogolyubov’Mitropolsky averaging method is used to plot amplitude’frequency response curves for steady-state vibrations. The steady-state vibrations at the frequency of principal harmonic resonance are analyzed for stability__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 2, pp. 52–59, February 2005. 相似文献
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Flexural modes are determined for initially bent cylindrical shells partially filled with a perfect incompressible liquid 相似文献
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E. K. Ankyanets 《International Applied Mechanics》2005,41(8):924-928
The vibrations of a cylindrical shell reinforced with ring ribs attached to the shell by means of elastic elements are studied.
The problem is solved by the finite-element method. The shell and ribs are modelled by a plane four-node finite element, which
is a combination of a four-node plane stress element and a four-node flexural element. The effect of the stiffness of the
elastic elements on the natural frequencies and modes is examined
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Translated from Prikladnaya Mekhanika, Vol. 41, No. 8, pp. 105–110, August 2005. 相似文献
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提出了一种分析交各向异性圆柱壳和阶梯圆柱壳稳定性问题的混合变量条形传递函数方法。首先基于Fluegge薄壳理论,通过定义广义位移变量和对应的广义力变量,建立了圆柱壳混合变量能量泛函;然后通过引入条形单元,定义混合状态变量和采用传递函数方法对超级壳单元求解,得到具有多种边界条件圆柱壳屈曲问题的半解析解;最后通过位移连续和力平衡条件,可以得到阶梯圆柱壳屈曲问题的解。理论解推导过程表明此方法在引入边界条件和进行阶梯圆柱壳求解时非常方便。算例分析的结果验证了本方法的正确性。 相似文献
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The results from studies into the vibrations and dynamic stability of thin elastic shells with initial geometric imperfections are analyzed. The corresponding dynamic problems are solved in both linear and nonlinear formulations. The influence of initial axisymmetric and nonaxisymmetric deflections on natural, forced, parametrically excited, and self-excited vibrations (flutter) is studied. The dynamic buckling of imperfect shells under short-term impulsive loading is examined. Some aspects of experimental investigation into the vibrations of shells with small geometric imperfections (deviations from the design shape) are considered 相似文献
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International Applied Mechanics - A refined statement of the coupled problem of axisymmetric resonant vibrations and self-heating of a shear compliant viscoelastic cylindrical shell with... 相似文献
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弹性地基上四边自由的各向异性矩形板 总被引:4,自引:2,他引:4
通过叠加法得到了弹性地基上的各向异性矩形板的一般解。每个叠加解被展成重傅立叶级数,其自身或其一阶导数在边界上的值被展成单傅立叶级数。利用控制微分方程和一些边界条件,每个叠加解被简化成用边界值的级数的系数表示的傅立叶级数。文后给出了弹性地基上的方板的挠曲面图。 相似文献