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Showing papers on "Thermoelastic damping published in 1989"


Journal ArticleDOI
TL;DR: In this paper, the authors used the Eshelby equivalent inclusion approach to provide a rigorous theoretical basis for the prediction of the mechanical properties of short fiber composites, and the equivalent inclusion construction which is central to this method is described in detail.

367 citations


Journal ArticleDOI
TL;DR: In this article, a micromechanics model is presented for the prediction of stress fields in coated fiber composites, based on the "average stress in the matrix" concept of Mori and Tanaka and formulated for the case of thermoelastic loading.

225 citations


Journal ArticleDOI
TL;DR: In this article, a laser-ultrasonic method to measure the acoustic velocities and the elastic constants of solid materials based on the crosscorrelation of successive echoes is presented.

157 citations


Journal ArticleDOI
TL;DR: In this article, a fundamental thermodynamic equation is derived for thermoelastic martensitic transformations, taking into account internal interaction between domains, the existence of interfaces and dissipative effects associated with motion of boundaries.

144 citations


Journal ArticleDOI
TL;DR: In this article, a thermoplastic theory of fluid-filled porous materials is established, which incorporates the heat transportation by fluid flow through pores in addition to the difference between the thermal expansibility of the pore fluid and that of the solid skeleton.

142 citations


Book
30 Apr 1989
TL;DR: In this paper, the authors present a model of one-dimensional continuoustime mechanics with a linear model of motion and Strain Kinematics, which is similar to the one presented in this paper.
Abstract: 1. One-Dimensional Continuum Mechanics.- 1.1. Kinematics of Motion and Strain.- 1.2. Balance of Mass.- 1.3. Balance of Linear Momentum.- 1.4. Balance of Energy.- 1.5. General Balance.- 1.6. The Entropy Inequality.- 1.7. Example Constitutive Equations.- 1.8. Thermodynamic Restrictions.- 1.9. Small Departures from Thermodynamic Equilibrium.- 1.10. Small Departures from Static Equilibrium.- 1.11. Some Features of the Linear Model.- 2. Kinematics of Motion.- 2.1. Bodies and Deformations.- 2.2. Velocity, Acceleration, and Deformation Gradients.- 2.3. Transformation of Linear, Surface, and Volume Elements.- 2.4. Strain Kinematics.- 2.5. Infinitesimal Strain Kinematics.- References.- 3. Equations of Balance.- 3.1. Balance of Mass.- 3.2. Balance of Linear Momentum.- 3.3. Balance of Angular Momentum.- 3.4. Balance of Energy.- 3.5. The Entropy Inequality.- 3.6. Jump Equations of Balance-Material Versions.- References.- 4. Models of Material Behavior.- 4.1. Examples.- 4.2. Isothermal Elasticity-Thermodynamic Restrictions.- 4.3. Isothermal Elasticity-Material Frame Indifference.- 4.4. Isothermal Elasticity-Material Symmetry.- 4.5. Incompressible Isothermal Elasticity.- 4.6. Thermoelastic Material with Heat Conduction and Viscous Dissipation-Constitutive Assumptions.- 4.7. Thermoelastic Material with Heat Conduction and Viscous Dissipation-General Thermodynamic Restrictions.- 4.8. Thermoelastic Material with Heat Conduction and Viscous Dissipation-Equilibrium Thermodynamic Restrictions.- 4.9. Thermoelastic Material with Heat Conduction and Viscous Dissipation-Material Frame Indifference.- 4.10. Thermoelastic Material with Heat Conduction and Viscous Dissipation-Material Symmetry.- 4.11. Constitutive Equations for a Compressible, Conducting, Viscous Fluid.- 4.12. Constitutive Equations for an Isotropic Linear Thermoelastic Solid with Heat Conduction.- References.- 5. Materials with Internal State Variables.- 5.1. Constitutive Assumptions and Thermodynamic Results.- 5.2. Maxwell-Cattaneo Heat Conductor.- 5.3. Maxwellian Materials.- 5.4. Closing Remarks-Alternate Forms of the Entropy Inequality.- References.- Appendix A. Mathematical Preliminaries.- A.1. Vector Spaces.- A.2. Linear Transformations.- A.3. Inner Product Spaces.- A.4. Components of Vectors and Linear Transformations.- A.5. Cross Products, Determinants, and the Polar Decomposition Theorem.- A.6. Multilinear Functionals and Tensor Algebra.- A.7. Euclidean Point Spaces, Coordinate Systems.- A.8. Vector Analysis.- Appendix B. Representation Theorems.

93 citations


Journal ArticleDOI
TL;DR: In this article, the problem of photoacoustic pulse generation is treated using generalized thermoelastic equations, specifically incorporating the hyperbolic heat conduction equation to avoid an infinite thermal propagation velocity.
Abstract: The problem of photoacoustic pulse generation is treated using generalized thermoelastic equations, specifically incorporating the hyperbolic heat conduction equation to avoid an infinite thermal propagation velocity. The assumption of equality of longitudinal and thermal velocities leads to a simplification of the solution in certain limiting cases, enabling insights into the character of the solution, without appreciably affecting the numerical results. The effect(s) of approximations made by previous authors may also be assessed. Numerical Hankel–Laplace transform inversion is shown to be practical for the general case, allowing such calculations to be duplicated by others.

62 citations


Journal ArticleDOI
TL;DR: In this article, a closed-form solution was derived for the displacement and velocity space-time correlation function of the Bresse-Timoshenko beam with transverse damping, generalizing the corresponding result by Eringen for the classical Bernoulli-Euler beam.

50 citations


Journal ArticleDOI
TL;DR: In this article, a transient thermal stress analysis of a laminated beam made of different materials in multilayers is presented, where the heat conduction problem is treated as a one-dimensional case in the direction of thickness and the transient temperature solution using the Laplace transform method.
Abstract: This paper concerns a transient thermal stress analysis of a laminated beam made of different materials in multilayers. To simplify the problem, we treat the heat conduction problem as a one-dimensional case in the direction of thickness; then we evaluate the transient temperature solution using the Laplace transform method. For the thermoelastic fields, we obtain the thermal stress distributions by using the elementary beam theory and Airy's thermal stress function method. As an example, we carry out numerical calculations for a laminated beam made of five layers and then examine the numerical results.

48 citations


Journal ArticleDOI
TL;DR: In this paper, numerical solutions of the complete set of thermoelastic equations for GaAs in conventional LEC configuration show that the prevailing thermal stresses exceed by close to one order of magnitude the CRSS.

46 citations


Journal ArticleDOI
TL;DR: In this article, the propagation of generalized thermoelastic plane harmonic waves in homogeneous anisotropic media has been investigated and four types of waves, namely a quasilongitudinal, two quasitransverse, and a thermal wave, are found to exist.
Abstract: In this article, the propagation of generalized thermoelastic plane harmonic waves in homogeneous anisotropic media has been investigated. Four types of waves, namely a quasilongitudinal, two quasitransverse, and a thermal wave, are found to exist. The thermal mode, which was diffusive in nature in the nonthermal relaxation case, now becomes wavelike with a finite, though large, wave speed. The results obtained theoretically have been verified numerically and are represented graphically for a single crystal of magnesium.

Journal ArticleDOI
TL;DR: In this paper, a generalized formulation of generalized thermoelasticity based on the theories of Lord and Shulman and of Green and Lindsay is derived, and numerical calculations for temperature, displacement and stresses under the generalized formulation are carried out and compared with those of classical dynamic coupled theory.
Abstract: This paper deals with one-dimensional generalized thermoelasticity based on the theories of Lord and Shulman and of Green and Lindsay. A formulation of generalized thermoelasticity that combines both generalized theories is derived. The generalized thermoelastic problems for an infinite solid with a cylindrical hole and an infinite solid with a spherical hole are analyzed by means of the Laplace transform technique. Numerical calculations for temperature, displacement, and stresses under the generalized formulation are carried out and compared with those of classical dynamic coupled theory.

Journal ArticleDOI
TL;DR: In this paper, a method for computing the radiation from a thermal expansion source, generated at a solid surface by a laser pulse of finite width, is evaluated for two radial beam energy distributions.
Abstract: A method for computing the radiation from a thermal expansion source, generated at a solid surface by a laser pulse of finite width, is evaluated for two radial beam energy distributions. A theoretical expression for the impulse response is obtained for two components of the displacement at any point within the solid, and may be used to compute the field for an arbitrary time excitation. Numerical results are presented, and are compared to experimental results for generation by a pulsed laser.

Journal ArticleDOI
TL;DR: In this paper, a numerical method based on the finite element technique for calculating heat transfer in crystal growth furnaces is developed, which entirely relies upon external control parameters, such as the pulling rate and the power input, while internal heat exchange is calculated on the basis of geometrical and material properties of all constituents of the puller.

Journal ArticleDOI
TL;DR: A model relating the velocity shifts of surface acoustic waves (SAW) to the six tensor components of quasistatic stresses makes it possible to define a family of quartz cuts with potentially low stress and temperature sensitivities for oscillator applications.
Abstract: A model is presented, relating the velocity shifts of surface acoustic waves (SAW) to the six tensor components of quasistatic stresses. Stress sensitivity is then defined through six independent coefficients, whatever the origin of the stress (direct external forces, thermoelastic stresses) might be. These coefficients, depending on crystal anisotropy, are computed for different cut angles and propagation directions of quartz crystal, and represented as a contour-line mapping. The determination of SAW quartz cuts compensated for both planar isotropic stresses and first-order temperature effects make it possible to define a family of quartz cuts with potentially low stress and temperature sensitivities for oscillator applications. >

Journal ArticleDOI
TL;DR: In this article, a theoretical model for laser generation was developed for the thermo-elastic energy regime, which integrates over point source Green's functions, suitably spread throughout the illuminated region.
Abstract: The generation of elastic waves by illumination of a free metal surface with a laser pulse was studied to establish a quantitative basis for laser ultrasonics in nondestructive evaluation of surfaces. Experiments were carried out using a Q‐switched Nd:YAG laser for generation and a wideband piezoelectric sensor for detection. A theoretical model for laser generation was developed for the thermoelastic energy regime. This model integrates over point source Green’s functions, suitably spread throughout the illuminated region. Good agreement was found between experiment and theory for characteristics in both time and frequency domains, for surface waves excited in the thermoelastic regime. For a given laser pulse energy, the highest Rayleigh wave peak frequency and bandwidth occurred when the Gaussian laser‐beam half‐width a was reduced just enough to begin surface damage. Once such damage commenced, further spot size reduction slightly lowered the peak frequency. Quantitative agreement with theory was found...

Journal ArticleDOI
TL;DR: In this paper, the following properties of tetragonal Li 2 B 4 O 7 are reported: dielectric, electrostrictive, electrooptic, elastic, thermoelastic and piezoelastic constants, coefficients of thermal expansion and indices of refraction.
Abstract: New values for the following properties of tetragonal Li 2 B 4 O 7 are reported: dielectric, electrostrictive, electrooptic, elastic, thermoelastic and piezoelastic constants, coefficients of thermal expansion and indices of refraction. These values are considered to be of superior precision compared to earlier published data

Proceedings ArticleDOI
31 Jul 1989
TL;DR: An enhanced theory for stress analysis of isotropic materials was developed in this article, which encompasses nonlinear thermoelastic, thermoplastic, and specimen motion effects, including cyclic plasticity analysis, high-temperature stress analysis, and residual stress analysis.
Abstract: An enhanced theory for Thermographic Stress Analysis of isotropic materials is developed. This theory encompasses nonlinear thermoelastic, thermoplastic and specimen motion effects. With this theory, several new applications for Thermographic Stress Analysis are possible including cyclic plasticity analysis, high-temperature stress analysis, and residual stress analysis. Examples of each of these applications are presented.

Journal ArticleDOI
TL;DR: In this article, the problem of heat conduction of a cylindrical medium composed of two different materials is considered in the framework of generalized thermoelasticity theory with one relaxation time.
Abstract: The problem of heat conduction of thermoelastic cylindrical medium composed of two different materials is considered. The problem is solved in the framework of the generalized thermoelasticity theory with one relaxation time. The solution is obtained in the Laplace transform domain using the potential function approach. Numerical inversion formula is used to obtain the corresponding solutions in the physical domain.

Journal ArticleDOI
TL;DR: In this article, the contact between two plates under the action of a force and temperature field is formulated, and the equations of motion and heat conduction of the thermoelastic plates are derived by expanding the three-dimensional equations in series in Legendre polynomials.

Journal ArticleDOI
TL;DR: In this paper, the use of thermal emission measurements as a means of assessing severity of damage and monitoring damage growth in composite materials is examined, experimentally and numerically, and the thermal emission profile reflects the interaction of load, geometry, material and damage in a nondestructive fashion.

Journal ArticleDOI
TL;DR: In this article, the authors extend the plane stress theory of Michell (1900, Proc. R. Math. Soc.A324, 565-594) for a laminated plate, to include stretching and bending solutions for an inhomogeneous thermoelastic plate.

Proceedings ArticleDOI
31 Jul 1989
TL;DR: In this article, the authors describe an experimental technique whereby the behavior of coatings, used to enhance surface properties of structures for thermoelastic stress analysis, may be assessed under a wide range of conditions.
Abstract: This paper describes an experimental technique whereby the behaviour of coatings, used to enhance surface properties of structures for thermoelastic stress analysis, may be assessed under a wide range of conditions. Established theoretical models are discussed and a novel description of the thermal response of coatings, with respect to changes in the substrate temperature, is presented. This description is then developed to include effects due to the thermoelastic response of the coating material and also the opacity of the coating to infra-red radiation. This work has substantial and wide ranging implications for the application of the thermoelastic technique. These are discussed briefly.

Journal ArticleDOI
TL;DR: In this article, a simple and efficient method for the solution of uncoupled transient thermoelastic problems using boundary integral techniques is presented, which employs a Laplace transformation to remove temporarily the time dependence of the governing equations.
Abstract: A simple and efficient method for the solution of uncoupled transient thermoelastic problems using boundary integral techniques is presented. The method employs a Laplace transformation to remove temporarily the time dependence of the governing equations. Numerical analysis is then carried out in the transform space, and results in the time-position space are found by numerical inversion of the Laplace transform. The method has the advantage that it avoids time-stepping and the costly evaluation of domain integrals. Boundary element and analytic solutions are compared, and the effect of cooling on the stresses around a deep underground opening is examined.

Proceedings ArticleDOI
31 Jul 1989
TL;DR: The thermoelastic effect described by Lord Kelvin describes the change in temperature of a body as it undergoes a change in stress under adiabatic conditions as mentioned in this paper, and it was first quantified by LORD Kelvin.
Abstract: The thermoelastic effect, first quantified by Lord Kelvin, describes the change in temperature of a body as it undergoes a change in stress under adiabatic conditions. The thermoelastic equation as described by Kelvin is given in eqn(1.1),

Journal ArticleDOI
TL;DR: In this article, it was shown that for all positive values of the frequency of the sinusoidal wave, the material is linearly stable in the sense that sinusoid waves may not increase without bound in the direction of propagation.
Abstract: Equations are written down governing the propagation of plane sinusoidal waves of small amplitude through a homogeneously prestrained equilibrium state of a materially homogeneous thermoelastic body of arbitrary elastic and thermal symmetry. The symmetric isothermal and isentropic acoustic tensors are defined in the usual way and it is assumed that the former is positive definite, so that it has three real and positive eigenvalues. It is shown, under the usual assumption that the specific heat at constant deformation is positive, that the three real and positive eigenvalues of the isentropic acoustic tensor are interlaced with those of the isothermal acoustic tensor, the smallest eigenvalue belonging to the isothermal and the largest to the isentropic acoustic tensor. Under the additional assumption that the symmetrized thermal conductivity tensor is positive definite, it is further shown that this result on the interlacing of the eigenvalues is sufficient to guarantee, for all positive values of the frequency of the sinusoidal waves, that the material is linearly stable in the sense that sinusoidal waves may not increase without bound in the direction of propagation. In the final section, the wide diversity in behaviour of the complex squared wave speed as a function of frequency is illustrated graphically. The stability result is extended to negative frequencies as these would be required in any Fourier synthesis of the sinusoidal wave solutions. A connection with Whitham's wave hierarchy approach is mentioned.

Journal ArticleDOI
TL;DR: In this article, a general finite element model is proposed to deal with the transient response in an axi-symmetric infinitely long elastic circular cylinder subjected to arbitrary thermal loadings over a finite band of the cylindrical surface by generalized coupled thermoelastic theory.

Journal ArticleDOI
TL;DR: In this article, the authors deal with the two-dimensional thermoelastic problem of interface thermally insulated crack in a microperiodic layered space, and the exact solution of the considered problem is obtained by using the complex potentials method.
Abstract: This paper deals with the two-dimensional thermoelastic problem of interface thermally insulated crack in a microperiodic layered space. Within the framework of the homogenized model of the linear thermoelasticity with microlocal parameters [10]–[13] the exact solution of the considered problem is obtained by using the complex potentials method [13]. The stress singularities at the crack tips are discussed.

Journal ArticleDOI
TL;DR: In this article, the authors presented a mathematical model for the damping of flow and pressure in the water hammer phenomenon, taking into account the dynamic structure of water column motion in a pressurized pipe for a compressible fluid, as well as the energy losses in the elastic walls of the pipe.
Abstract: The Darcy-Weisbach formula, used in the majority of mathematic models for calculating the head losses in the unsteady motion of water does not simulate with sufficient accuracy the damping of flow and pressure in the water hammer phenomenon Taking into account the dynamic structure of water column motion in a pressurized pipe, for a compressible fluid, as well as the energy losses in the elastic walls of the pipe, we present for the calculation of the flow and pressure oscillation damping a formula based on the structural (hysteretic) friction forces [6, 13] In the case of elastic bodies the structural damping forces are proportional to the elastic forces, but a quarter of a period phase out By putting into practice the presented formula a good agreement between computations and experimental measurements is achieved

Journal ArticleDOI
TL;DR: In this paper, a lamination tailoring technique is proposed in order to control a coefficient of thermal expansion of graphite-epoxy composites in a principal direction, consisting of two concepts of the thermoelastic invariants and the lamination parameters.
Abstract: A lamination tailoring technique is proposed in order to control a coefficient of thermal expansion of graphite-epoxy composites in a principal direction. This technique consists of two concepts of the thermoelastic invariants and the lamination parameters. The expansion free condition yields to a parabola in the feasible region of the lamination parameters. The calculated curves for a wide range of temperatures intersect almost at a point. A laminate with the lay-up construction corresponding to this point will exhibit an approximately null coefficient of thermal expansion in one direction in that temperature range. Some preliminary experimental results indicate that the present procedure is possible and promising. The tailored material will be appropriate for the space station structure.