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1.
基于厚板理论分析深水域中弹性浮板的水波响应 总被引:1,自引:1,他引:0
基于线性水波理论和Mindlin厚板动力学理论,采用Wiener-Hopf 方法,研究了不同水深水面上弹性浮板在不同入射波数水波作用下的动力学响应问题。首先推导了无限深水域中弹性浮板水波响应的解析解,并将本文分析计算结果与采用其他方法(经典薄板理论)得到的计算结果进行了对比和分析;其次,采用本文方法研究了大型浮板在三种入射波数的水波作用下动弯矩幅值的分布情况;最后,根据其他文献的方法计算了不同水深(有限水深)情况下浮板的动响应,并与本文的计算结果进行了对比分析。 相似文献
2.
IntroductionAsawell-establishedandsophisticatednumericalanalysistechniqueforthedifferentialequahons,thefiniteelementmethodwasoriginatedindependentlybythedomesticandtheforeignmechanicalinvestigatorstheyyearsago.ItfoundforthefirsttimewideapplicationsintheelasticstfUctolproblemsandwiththedevelopmentofcomputerextendedinvaryingdegreestOalmostalltheengineeringdisciplinesandmanyscientificandtechnologicalfields.Thisleadstoadramaticbreakthroughforthecurrentcomputationalmathematics.Themathematicalbasis… 相似文献
3.
L. A. Tkacheva 《Journal of Applied Mechanics and Technical Physics》2005,46(2):230-238
The Wiener-Hopf technique is used to obtain an analytical solution for the problem of vibrations of a floating semi-infinite elastic plate due to earthquake-induced vibrations of a bottom segment. An explicit solution is obtained ignoring the inertial term. The surface-wave amplitudes and ice-plate deflection are studied numerically as functions of the frequency and position of the vibrating bottom segment, ice thickness, and fluid depth.Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 46, No. 2, pp. 98–108, March–April, 2005. 相似文献
4.
基于文献[8]给出的平板弯曲振动精确化方程,对含圆孔平板中弹性波散射与动应力集中问题进行了研究.文中给出了分别基于Mindlin板与精确化板方程在不同参数下圆孔动弯矩集中系数的数值结果,并对结果进行了对比分析和讨论.结果表明:在较低频率和薄板情况下,基于文献[8]的方程与基于Mindlin板理论得到的动弯矩结果是基本一致的;在较高频率和厚板情况下,基于文献[8]的方程与基于Mindlin板理论的动弯矩结果相差较大,最大值超出可达16%.由于文献[8]给出的平板振动精确化方程是在没有任何工程假设条件下得到的,因此其分析计算结果更精确一些. 相似文献
5.
Two-dimensional problem of periodic loading of an elastic plate floating on the surface of an infinitely deep fluid 总被引:2,自引:0,他引:2
The action of external periodic pressure on an elastic plate floating on the surface of a fluid assumed to be ideal and incompressible
is examined by the method of normal modes in the linear formulation. The behavior of the matrix of coefficients of the hydrodynamic
load on the plate is considered in detail for different frequencies. The behavior of the plate under localized periodic loading
is compared for the cases of a heavy fluid with a finite or infinite depth and for a weightless infinite-depth fluid.
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Translated from Prikladnaya Mekhanika i Tekhnicheskaya Fizika, Vol. 46, No. 3, pp. 61–72, May–June, 2005. 相似文献
6.
受损伤固体中含有的微裂纹或微孔洞往往具有周期性,对含周期性缺陷结构中的弹性波分析是力学研究中的重要课题,它直接关系到结构的强度和使用寿命。目前对损伤固体中弹性波散射与透射研究结果主要是弹性动力学平面问题。1995年。Scarpetta和Sumbatyan采用解析法研究了平面波在双周期裂纹弹性介质中的传播问题。并推出显式分析结果。本文基于弹性动力学理论,分析研究了含有单排横向周期裂纹的平板中弯曲波的反射与透射问题。给出了含单排裂纹时反射波与透射波系数的数值结果。对于多排裂纹情况,可采用具有退化核第一类Fredholm积分方程方法分析求解,在求解中给出相应的无量纲数,例如无量纲波数、裂纹尺寸比等。本文分析结果可望能在工程振动控制中应用。 相似文献
7.
The reflection and transmission of obliquely incident Rayleight surface waves by an interphase between two quarter spaces
of identical or different materials, have been investigated. The mechanical behavior of the interphase is represented by a
thin viscoelastic layer. By using the full space Green's functions due to a spatially harmonic line load, the mathematical
statement of the 3-dimension problem is reduced to a 2-dimension system of singular integral equations. The far-field behavior
of the scattered waves leads to the definition of reflection and transmission coefficients,R andT. The system of the singular integral equations are solved forR andT with the boundary element method. The results are presented for selected values of the elastic constants of the joined quarter
spaces, the parameters of the interphase and the incident angles of Rayleigh surface waves. 相似文献
8.
An exact solution is proposed in this paper based on the elasticity theory for sound reflection from an infinite laminated plate and transmission through it, and some phenomena of sound propagation in an isotropic media are also discussed. Some examples given here could be used to test approximate models of laminated plates. 相似文献
9.
The propagation of elastic waves is studied in a porous solid saturated with two immiscible viscous fluids.The propagation of three longitudinal waves is represented through three scalar potential functions.The lone transverse wave is presented by a vector potential function.The displacements of particles in different phases of the aggregate are defined in terms of these potential functions.It is shown that there exist three longitudinal waves and one transverse wave.The phenomena of reflection and refraction due to longitudinal and transverse waves at a plane interface between an elastic solid half-space and a porous solid half-space saturated with two immiscible viscous fluids are investigated.For the presence of viscosity in pore-fluids,the waves refracted to the porous medium attenuate in the direction normal to the interface.The ratios of the amplitudes of the reflected and refracted waves to that of the incident wave are calculated as a nonsingular system of linear algebraic equations.These amplitude ratios are used to further calculate the shares of different scattered waves in the energy of the incident wave.The modulus of the amplitude and the energy ratios with the angle of incidence are computed for a particular numerical model.The conservation of the energy across the interface is verified.The effects of variations in non-wet saturation of pores and frequencies on the energy partition are depicted graphically and discussed. 相似文献
10.
Based on complex variables and conformal mapping, the elastic wave scat- tering and dynamic stress concentrations in the plates with two holes are studied by the refined dynamic equation of plate bending. The problem to be solved is changed to a set of infinite algebraic equations by an orthogonM function expansion method. As examples, under free boundary conditions, the numerical results of the dynamic moment concen- tration factors in the plates with two circular holes are computed. The results indicate that the parameters such as the incident wave number, the thickness of plates, and the spacing between holes have great effects on the dynamic stress distributions. The results are accurate because the refined equation is derived without any engineering hypothese. 相似文献
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12.
基于Reissner-Mindlin一阶剪切变形理论,讨论在预加面内机械荷载作用下,弹性半空间地基上四边自由中厚矩形板的横向振动问题。把地基看作三维弹性半空间体,考虑地基变形的衰减。用一组数学上完备的二元多项式作为位形函数,采用pb-2 Rayleigh-Ritz法求得四边自由中厚矩形板的自振频率和在横向简谐荷载作用下的动力响应。讨论了板的长宽比、宽厚比及弹性地基和板的相对刚度对板的自振频率的影响。 相似文献
13.
在轴向应力波传播和反射过程中弹性有限长圆柱壳非对称动态屈曲 总被引:2,自引:0,他引:2
本文讨论弹性有限长圆柱壳端部受冲击载荷作用,在轴向应力波传播和反射过程中的非对称动态屈曲问题。通过建立和求解扰动方程得到了动态屈曲的分叉条件,临界载荷和屈曲模态。数值结果表明:当壳壁厚不很薄时,轴对称屈曲临界载荷比非轴对称临界载荷高;反之,轴对称临界载荷会比非对称临界载荷低;由于应力波的反射,临界载荷降低,因而更容易发生屈曲,屈曲模态也有其不同特点。 相似文献
14.
横观各向同性饱和地基上中厚圆板的非轴对称振动 总被引:1,自引:0,他引:1
研究横观各向同性饱和土地基上中厚弹性圆板的非轴对称振动问题。基于横观各向同性饱和介质Biot波动方程的一般解,按混合边值问题建立了饱和地基与弹性中厚圆板非轴对称动力相互作用的对偶积分方程,并将对偶积分方程转化为易于计算的第二类Fredholm积分方程;采用数值方法求解该积分方程。数值算例结果表明,当h/a>0.05时,饱和半空间体上中厚度圆板在不同频率下的振动特性与相应频率下的刚性板的振动特性基本相同,当h/a<0.05时,板中心的位移将随h/a的减小而增大。 相似文献
15.
P. MAITI P.RAKSHIT S. BANERJEA 《应用数学和力学(英文版)》2011,32(5):635-644
The present paper is concerned with scattering of water waves from a vertical plate, modeled as an elastic plate, submerged
in deep water covered with a thin uniform sheet of ice. The problem is formulated in terms of a hypersingular integral equation
by a suitable application of Green's integral theorem in terms of difference of potential functions across the barrier. This
integral equation is solved by a collocation method using a finite series involving Chebyshev polynomials. Reflection and
transmission coefficients are obtained numerically and presented graphically for various values of the wave number and ice-cover
parameter. 相似文献
16.
17.
Ch. Midya M. Kanoria B. N. Mandal 《Archive of Applied Mechanics (Ingenieur Archiv)》2001,71(12):827-840
Summary The problem of water wave scattering by an inclined thin plate submerged in water of uniform finite depth is investigated
here under the assumption of irrotational motion and linear theory. A hypersingular integral equation formulation of the problem
is obtained by an appropriate use of Green's integral theorem followed by utilization of the boundary condition on the plate.
This hypersingular integral equation involves the discontinuity in the potential function across the plate, which is approximated
by a finite series involving Chebyshev polynomials. The coefficients of this finite series are obtained numerically by collocation
method. The quantities of physical interest, namely the reflection and transmission coefficients, force and moment acting
on the plate per unit width, are then obtained numerically for different values of various parameters, and are depicted graphically
against the wavenumber. Effects of finite-depth water, angle of inclination of the plate with the vertical over the deep water
and vertical plate results for these quantities are shown. It is observed that the deep-water results effectively hold good
if the depth of the mid-point of the submerged plate below the free surface is of the order of one-tenth of the depth of the
bottom.
Received 30 November 2000; accepted for publication 26 June 2001 相似文献
18.
A procedure of deriving nonlinear wave equations that describe the propagation and interaction of hyperelastic cylindrical
waves in composite materials modeled by a mixture with two elastic constituents is outlined. Nonlinearity is introduced by
metric coefficients, Cauchy-Green strain tensor, and Murnaghan potential. It is the quadratic nonlinearity of all governing
relations. For a configuration (state) dependent on the radial coordinate and independent of the angular and axial coordinates,
quadratically nonlinear wave equations for stresses are derived and a relationship between the components of the stress tensor
and partial strain gradient is established. Four combinations of physical and geometrical nonlinearities in systems of wave
equations are examined. Nonlinear wave equations are explicitly written for three of the combinations
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Translated from Prikladnaya Mekhanika, Vol. 43, No. 6, pp. 63–72, June 2007. 相似文献
19.
Huang Yuying 《Acta Mechanica Sinica》1988,4(3):275-283
Based on Reissner's plate theory, a localized variational principle for the coupled vibrations of moderately thick floating
plates seated on the sea floor with variable water depth is presented in this paper. It will be a powerful tool to formulate
various approximate methods of moderately thick floating plates. By means of this variational principle a formula for calculating
the natural frequencies of moderately thick floating plates is also obtained. A numerical example shows that high accuracy
and computational time saving may be achieved in calculation. 相似文献
20.
范家参 《应用数学和力学(英文版)》2000,21(3):335-340
IntroductionThegoverningequationsforaninvertedelasticthinshallowshellonelastichafspaceinstaticbendingare[1]4-Eihi2kw=02=2/x2 2/y2,2k=ky(2/x2) kx(2/y2),(1)Di4w 2k=q-p,(2)w(x,y)=λe 2Ge4πGe(λe Ge)∫∫sp(ξ,η)dξdη(x-ξ)2 (y-η)2,(3)whereinEqs.(1),(2)and(3),w(x,y)isthedeflectionoftheshell,(x,y)isthem… 相似文献