共查询到20条相似文献,搜索用时 15 毫秒
1.
I. F. Kirichok 《International Applied Mechanics》2011,46(8):890-901
The coupled problem of forced vibrations and self-heating of thermoviscoelectroelastic shells of revolution with piezoceramic
sensor and actuator under monoharmonic loading is solved. The temperature dependence of the complex characteristics of the
passive and piezoactive materials is taken into account. The coupled nonlinear problem of thermoelectroelasticity is solved
by time-marching integration, using discrete orhogonalization to integrate the equations of elasticity and explicit finite
differencing to solve the heat conduction equation. The effect of the dimensions of the sensor and actuator and self-heating
on the sensor voltage and on the active damping of forced vibrations of a circular plate under uniform monoharmonic transverse
pressure is studied 相似文献
2.
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
3.
The forced monoharmonic vibrations and self-heating of a circular thermoviscoelastic plate with piezoelectric sensor and actuator
are studied. The viscoelastic behavior of the passive (without piezoeffect) and piezoactive materials is described using the
concept of complex moduli. The problems of electroelasticity and heat conduction are solved numerically, assuming that the
mechanical load is unknown. The effect of self-heating on the active damping of the vibrations of the plate is analyzed 相似文献
4.
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
5.
I. F. Kirichok 《International Applied Mechanics》2009,45(2):215-222
The bending vibration and dissipative heating of a viscoelastic isotropic ring plate with piezoceramic actuators under electromechanical
loading and shear deformation are studied by solving a coupled problem. The temperature dependence of the complex characteristics
of the passive and piezoactive materials is taken into account. The nonlinear problem of thermoviscoelasticity is solved by
time stepping with discrete orthogonalization used at each iteration to integrate the equations of elasticity and using an
explicit finite-difference scheme to solve the heat-conduction equation with a nonlinear heat source. The effect of shear
deformation, fixation conditions for the plate, the geometry of the piezoactuators, and the dissipative-heating temperature
on the active damping of the forced vibration of a circular plate subject to uniform transverse monoharmonic compression is
studied
Translated from Prikladnaya Mekhanika, Vol. 45, No. 2, pp. 124–132, February 2009. 相似文献
6.
Katica? Hedrih 《Archive of Applied Mechanics (Ingenieur Archiv)》2008,78(9):725-735
Based on the author’s previously published results for transversal free vibrations of axially moving sandwich belts described
by coupled partial differential equations, which are derived and analytically solved, this paper contains new analytical results,
for forced vibrations of the same system excited by transversal external excitation. The transversal forced vibrations of
the axially moving sandwich belts are described by the coupled partial nonhomogeneous differential equations. The partial
differential equations are analytically solved. Bernoulli’s method of particular integrals and Lagrange’s method of the variations
of the constants are used. 相似文献
7.
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
8.
Yaroslav Alexander Zhuk I. A. Guz C. M. Sands 《Archive of Applied Mechanics (Ingenieur Archiv)》2011,81(2):215-227
A coupled dynamic problem of electromechanics for thin wall multilayer elements is formulated based on the Kirchhoff–Love
hypotheses. In the case of harmonic loading, a simplified formulation is given using the monoharmonic approach and the concept
of complex moduli to characterize the cyclic properties of the material. The problem of forced vibrations of three-layer beam,
whose outer layers are made of a viscoelastic piezoactive material, and, the inner layer of a passive physically nonlinear
material, is considered as an example to demonstrate the possibility of the technique elaborated. The possibility of damping
the forced vibrations of a structure with the help of harmonic voltages applied to the external piezoactive layers is studied.
Results obtained for the transient response of the beam using the complete model are compared with data found using the simplified
model. Limitations on the simplified model application are specified. 相似文献
9.
The paper addresses the forced flexural vibrations and dissipative heating of a circular viscoelastic plate with piezoactive
actuators under axisymmetric loading. A refined formulation of this coupled problem is considered. The viscoelastic behavior
of materials is described using the concept of complex moduli dependent on the temperature of dissipative heating. The electromechanical
behavior of the plate is modeled based on the Timoshenko hypotheses for the mechanical variables and analogous hypotheses
for the electric-field variables in the piezoactive layers of the actuator. The temperature is assumed constant throughout
the thickness. The nonlinear problem is solved by a time stepping method using, at each step, the discrete-orthogonalization
and finite-difference methods to solve the elastic and heat-conduction equations, respectively. A numerical study is made
of the effect of the shear strain, the temperature dependence of the material properties, fixation conditions, and geometrical
parameters of the plate on the vibrational characteristics and the electric potential applied to the actuator electrodes to
balance the mechanical load
Translated from Prikladnaya Mekhanika, Vol. 44, No. 9, pp. 104–114, September 2008. 相似文献
10.
The forced vibrations of a cylindrical orthotropic shell are studied. Two types of boundary conditions on the outer surface
are examined considering that the displacement vector prescribed on the inner surface varies harmonically with time. Asymptotic
solutions of associated dynamic equations of three-dimensional elasticity are found. Amplitudes of forced vibrations are determined
and conditions under which resonance occurs are established. Boundary-layer functions are defined. The rate of their decrease
with distance from the ends inside the shell is determined. A procedure of joining solutions for the internal boundary-layer
problem is outlined in the case for the, if clamping boundary conditions are prescribed at the ends 相似文献
11.
A strongly non-linear dynamic problem of thermomechanics for multilayer beams is formulated based on the Kirchhoff–Love hypotheses. In the case of harmonic loading, a simplified formulation is given using a single-frequency approximation and the concept of complex moduli to characterise the non-linear cyclic properties of the material. As an example, the problem of forced vibrations and dissipative heating of a roller-supported layered beam containing piezoactive layers is solved. Different aspects of thermal, mechanical and electric responses to the mechanical and electric excitations are addressed. Dissipative heating due to electromechanical losses in the three-layer beam with piezoelectric layers is studied. It is assumed that the structure fails if the temperature exceeds the Curie point for piezoceramics. Using this criterion, the fatigue life of the structure is estimated. Limitations of the approximate monoharmonic approach are also specified. 相似文献
12.
An approximate formulation is given to a dynamic coupled thermomechanical problem for physically nonlinear inelastic thin-walled structural elements within the framework of a geometrically linear theory and the Kirchhoff–Love hypotheses. A simplified model is used to describe the vibrations and dissipative heating of inhomogeneous physically nonlinear bodies under harmonic loading. Nonstationary vibroheating problem is solved. The dissipative function obtained from the solution for steady-state vibrations is used to simulate internal heat sources. For the partial case of forced vibrations of a beam, the amplitude–frequency characteristics of the field quantities are studied within a wide frequency range. The temperature characteristics for the first and second resonance modes are compared. 相似文献
13.
Based on Donnell shallow shell equations, the nonlinear vibrations and dynamic instability of axially loaded circular cylindrical shells under both static and harmonic forces is theoretically analyzed. First the problem is reduced to a finite degree-of-freedom one by using the Galerkin method; then the resulting set of coupled nonlinear ordinary differential equations of motion are solved by the Runge–Kutta method. To study the nonlinear behavior of the shell, several numerical strategies were used to obtain Poincaré maps, Lyapunov exponents, stable and unstable fixed points, bifurcation diagrams, and basins of attraction. Particular attention is paid to two dynamic instability phenomena that may arise under these loading conditions: parametric excitation of flexural modes and escape from the pre-buckling potential well. Calculations are carried out for the principal and secondary instability regions associated with the lowest natural frequency of the shell. Special attention is given to the determination of the instability boundaries in control space and the identification of the bifurcational events connected with these boundaries. The results clarify the importance of modal coupling in the post-buckling solution and the strong role of nonlinearities on the dynamics of cylindrical shells. 相似文献
14.
A. G. Gorshkov É. I. Starovoitov A. V. Yarovaya 《International Applied Mechanics》2001,37(9):1196-1203
The free and forced harmonic vibrations of viscoelastoplastic sandwich shells are analyzed. An equation for approximate determination of the amplitudes of near-resonance vibrations is derived. As an example, the problem is solved for a sandwich circular cylindrical shell 相似文献
15.
The equations of nonaxisymmetric vibrations of sandwich cylindrical shells with discrete core under nonstationary loading are presented. The components of the elastic structure are analyzed using a refined Timoshenko theory of shells and rods. The numerical method used to solve the dynamic equations is based on the integro-interpolation method of constructing finite-difference schemes for equations with discontinuous coefficients. The dynamic problem for a sandwich cylindrical shell under distributed nonstationary loading is solved with regard for the discreteness of the core__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 2, pp. 60–67, February 2005. 相似文献
16.
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
17.
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
18.
A. D. Zamanov 《International Applied Mechanics》2001,37(9):1189-1195
A problem on the forced vibrations of a rectangular composite plate with locally curved structures is formulated using the exact three-dimensional equations of continuum mechanics and continuum theory. A technique for numerical solution of the problem is developed based on the semianalytic finite-element method. Numerical results are given for the stress distribution in the plate under forced vibrations. The results obtained are analyzed to study the effect of the curvature in the structure of the plate on the distribution of stress amplitudes. It is shown that the curvatures change significantly the stress pattern under either static or dynamic loading 相似文献
19.
P. S. Koval’chuk 《International Applied Mechanics》2005,41(4):405-412
The Bogolyubov-Mitropolsky method is used to find approximate periodic solutions to the system of nonlinear equations that describes the large-amplitude vibrations of cylindrical shells interacting with a fluid flow. Three quantitatively different cases are studied: (i) the shell is subject to hydrodynamic pressure and external periodical loading, (ii) the shell executes parametric vibrations due to the pulsation of the fluid velocity, and (iii) the shell experiences both forced and parametric vibrations. For each of these cases, the first-order amplitude-frequency characteristic is derived and stability criteria for stationary vibrations are established__________Translated from Prikladnaya Mekhanika, Vol. 41, No. 4, pp. 75–84, April 2005. 相似文献
20.
The basic equations of the theory of thermoviscoelastic thin-walled plates with piezoelectric sensors and actuators under
monoharmonic mechanical and electric loading are derived using the Kirchhoff–Love hypotheses. The thermomechanical behavior
of passive and piezoactive materials is described using the concept of complex characteristics. Methods of solving nonlinear
problems of active damping of thermomechanical vibrations of plates with sensors and actuators are considered. The effect
of dissipative heating on the damping of axisymmetric vibrations of a thermoviscoelastic solid circular plate is analyzed
as an example 相似文献