共查询到15条相似文献,搜索用时 8 毫秒
1.
I. F. Kirichok 《International Applied Mechanics》2005,41(9):1037-1042
The flexural vibrations and dissipative heating of a circular bimorph piezoceramic plate are studied. The plate is excited
by a harmonic electric field applied to nonuniformly electroded surfaces. The viscoelastic behavior of piezoceramics is described
in terms of temperature-dependent complex moduli. The nonlinear coupled problem of thermoviscoelasticity is solved by step-by-step
integration in time, using the discrete-orthogonalization method to solve the mechanics equations and the finite-differences
method to solve the heat-conduction equations. A numerical analysis is conducted for TsTStBS-2 piezoceramics to study the
influence of the nonuniform electroding on the resonant frequency, amplitude, and modes of flexural vibrations and the amplitude-
and temperature-frequency characteristics of the plate
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Translated from Prikladnaya Mekhanika, Vol. 41, No. 9, pp. 94–100, September 2005. 相似文献
2.
I. F. Kirichok 《International Applied Mechanics》2006,42(3):336-341
The forced flexural vibrations and dissipative heating of a bimorph ring plate are studied. The plate is made of viscoelastic
piezoceramics and is polarized across the thickness. The outer surfaces of the plate are nonuniformly electroded, and harmonic
electric excitation is applied to the electrodes. The viscoelastic behavior of the material is described using the concept
of temperature-dependent complex moduli. The coupled nonlinear problem of thermoviscoelasticity is solved by time iteration
using, at each iteration, the discrete-orthogonalization method to integrate the mechanics equations and the explicit finite-difference
method to solve the heat-conduction equation with a nonlinear heat source. Numerical calculations demonstrate that by changing
the size of the ring electrode we can influence the natural frequency, stress and displacement distributions, dissipative-heating
temperature, and amplitude-and temperature-frequency characteristics. With certain boundary conditions, there is an optimal
electrode configuration that produces deflections of maximum amplitudes when an electric excitation is applied
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Translated from Prikladnaya Mekhanika, Vol. 42, No. 3, pp. 102–109, March 2006. 相似文献
3.
The monoharmonic radial vibrations and dissipative heating of an infinite hollow piezoceramic cylinder are studied in dynamic formulation, taking into account the temperature dependence of the complex electromechanical characteristics over a wide range of temperatures, including depolarization temperatures. The influence of the heat exchange conditions, the level of electric load, and geometry on the thermoelectromechanical characteristics is studied in the case of forced vibrations at the first resonance__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 3, pp. 101–107, March 2005. 相似文献
4.
An analytic solution is obtained to describe the vibrations and dissipative heating of a simply supported infinite cylindrical panel under periodic normal loads moving over its surface with a constant velocity. Special attention is focused on resonant vibrations, which result in the most intensive dissipative heating. It is additionally assumed that the material of the panel is viscoelastic, its properties are independent of temperature, and Poisson’s ratio is real. The influence of thickness, radius of curvature, load velocity, and viscoelastic properties on the thermal state of the panel is analysed against the thermal state of the plate__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 4, pp. 100–109, April 2005. 相似文献
5.
The forced monoharmonic bending vibrations and dissipative heating of a piezoelectric circular sandwich plate under monoharmonic
mechanical and electrical loading are studied. The core layer is passive and viscoelastic. The face layers (actuators) are
piezoelectric and oppositely polarized over the thickness. The plate is subjected to harmonic pressure and electrical potential.
The viscoelastic behavior of the materials is described by complex moduli dependent on the temperature of heating. The coupled
nonlinear problem is solved numerically. A numerical analysis demonstrates that the natural frequency, amplitude of vibrations,
mechanical stresses, and temperature of dissipative heating can be controlled by changing the area and thickness of the actuator.
It is shown that the temperature dependence of the complex moduli do not affect the electric potential applied to the actuator
to compensate for the mechanical stress
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Translated from Prikladnaya Mekhanika, Vol. 44, No. 1, pp. 79–89, January 2008. 相似文献
6.
A coupled dynamic problem of thermoelectromechanics for thin-walled multilayer elements is formulated based on a geometrically nonlinear theory and the Kirchhoff–Love hypotheses. In the case of harmonic loading, an approximate formulation is given using the concept of complex moduli to characterize the cyclic properties of the material. The model problem on forced vibrations of sandwich beam, whose core layer is made of a passive physically nonlinear material, and face layers, of a viscoelastic piezoactive material, is considered as an example to demonstrate the possibility of damping the vibrations by applying harmonic voltage to the oppositely polarized layers of the beam. Substantiation is given for a linear control law with a complex coefficient for the electric potential, which provides damping of vibrations in the first symmetric mode at the linear and nonlinear stages of deformation. The stress–strain state and dissipative-heating temperature are studied 相似文献
7.
The Fourier method is used to find the analytical solutions to two-dimensional quasistatic problems of stationary polyharmonic vibrations and dissipative heating of a linearly viscoelastic cylinder. The influence of the cylinder thickness and the width of the loading area on the thermomechanical state of the cylinder is studied based on numerical data__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 2, pp. 23–32, February 2005. 相似文献
8.
The vibrations and dissipative heating of an infinite viscoelastic beam under a moving load are studied on the basis of Timoshenko beam theory. The influence of transverse-shear strain and rotary inertia on the critical velocities of the moving load, the amplitude of bending vibration, and the temperature of dissipative heating is analyzed__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 1, pp. 69–76, January 2005. 相似文献
9.
The dynamic thermomechanical problem for thin-walled laminated elements is formulated based on the geometrically linear theory and Kirchhoff–Love hypotheses. A simplified model of vibrations and dissipative heating of structurally inhomogeneous inelastic bodies under harmonic loading is used. The mechanical properties of materials are described using strain-dependent complex moduli. A nonstationary vibration-heating problem is solved. The dissipative function, derived from the stationary solution, is used to specify internal heat sources. The amplitude–frequency characteristics and spatial distributions of the main field variables are studied for a sandwich beam subjected to forced vibrations 相似文献
10.
Flexural vibrations and vibrational heating of a ring plate with thin piezoceramic pads under single-frequency electromechanical loading 总被引:1,自引:1,他引:0
I. F. Kirichok 《International Applied Mechanics》2008,44(2):200-207
The paper deals with the coupled problem of flexural vibrations and dissipative heating of a viscoelastic ring plate with
piezoceramic actuators under monoharmonic electromechanical loading. The temperature dependence of the complex characteristics
of passive and piezoactive materials is taken into account. The coupled nonlinear problem of thermoviscoelasticity is solved
by an iterative method. At each iteration, orthogonal discretization is used to integrate the equations of elasticity and
an explicit finite-difference scheme is used to solve the heat-conduction equation with a nonlinear heat source. The effect
of the dissipative heating temperature, boundary conditions, and the thickness and area of the actuator on the active damping
of the forced vibrations of the plate under uniform transverse harmonic pressure is examined
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Translated from Prikladnaya Mekhanika, Vol. 44, No. 2, pp. 99–108, February 2008. 相似文献
11.
The vibrations and self-heating of a layered metal-polymer rectangular prism kinematically excited by a normally vibrating
punch are analyzed numerically. The effect of reinforcement layers on the rate of variation in and the spatial distribution
of the temperature field is examined. It is established that thin metallic layers in a polymer matrix change the dissipation
mechanism from shear to bulk. The effect of contact stress concentration on the localization of temperature field is studied.
It is established that the energy flux through the load application area decreases due to softening of the material. Several
reinforcement effects are revealed. It is shown that they are determined by the value of the load parameter. The numerical
results are in good agreement with experimental data on self-heating kinetics
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Translated from Prikladnaya Mekhanika, Vol. 43, No. 8, pp. 71–79, August 2007. 相似文献
12.
É. I. Starovoitov D. V. Leonenko A. V. Yarovaya 《International Applied Mechanics》2003,39(12):1458-1463
The paper studies axisymmetric resonance vibrations of an elastic circular sandwich plate under local periodic surface loads of rectangular, sinusoidal, and parabolic forms. The hypotheses of broken normal are used to describe the kinematics of the plate, which is asymmetric in thickness. The core is assumed to be light. The initial–boundary-value problems are solved analytically. The solutions are analyzed 相似文献
13.
The nonlinear response of rectangular and square metallic plates subjectto transverse harmonic excitations is studied. The nonlinearitiesoriginate from the use of Von Kármán strains. The method of multiplescales is used to solve the system of differential equationsapproximately. Frequency response curves are presented for both squareand rectangular plates for primary resonance of either mode in thepresence of a one-to-one internal resonance. Stability of steady statesolutions is investigated. Bifurcation points and their types arediscussed. 相似文献
14.
15.
建立导电射流在径向电场作用下的线性稳定性粘性模型,通过正则模方法,推导了轴对称和非轴对称模态下的色散关系,通过计算求得增长率随波数及电欧拉数的变化,并在理论上预测了最有可能波长.选用酒精和酒精甘油混合物作实验液体,观察了径向电场对射流不稳定性行为的影响规律,并测量射流表面波的波长.实验结果和理论结果在定性方面取得了较好的一致.但通过与实验比较,理论预测的最有可能波长在非轴对称模态出现较大偏差,普遍比实验结果小.而且,实验表明,最大增长率并不是判断主导模态的好标准,因为在非轴对称的最大增长率小于轴对称的最大增长率情况下,实验显示非轴对称模态要比轴对称模态明显了.因此,对于非轴对称的不稳定机理,需要进一步研究.对轴对称模态,理论给出了较好的预测. 相似文献