Magneto-elastic transverse surface waves in an internal stratum

Transverse surface waves in a stratum of uniform thickness, bounded on both sides by very deep layers of different materials, are investigated in the context of magneto-elasticity. Assuming that all the three materials are perfect conductors of electricity, it is found that the waves can exist for all orientations of the initial magnetic field and that the field increases, in general, the bounds for phase velocity. Other effects of the field on the physical properties of the material and on the phase velocity and frequency of waves are also considered in detail. © 1977 Indian Academy of Sciences

Mechanocaloric effect on magnetothermoelastic interactions in a cylindrical conductor carrying an electric current

The mechanocaloric effect on magnetothermoelastostatic interactions in a cylindrical conductor carrying a uniform electric current is investigated. It is found that this effect reduces the Joule heating effect and induces non-linearity into the behavior of stresses. A condition under which the mechanocaloric effect nullifies the Joule effect is also obtained. © 1978 Taylor & Francis Group, LLC

On plane strain problems in magneto-thermo-visco-elasticity

Plane strain problems on magneto-thermo-visco-elastic interactions in a parallel union of the Kelvin and Maxwell bodies are investigated using the basic equations of electrodynamics and thermo-visco-elasticity. Assuming that the applied magnetic field is transverse to the plane of deformation and that the material is a perfect conductor of electricity, it is seen that the heat sources and the potential part of the body forces produce longitudinal waves only and the rotational part of the body forces gives rise to transverse waves only. The effect of deformation on magnetic permeability is equivalent to an anisotropic rescaling of the primary magnetic field. The effect of the applied magnetic field on waves produced by a plane heat source is equivalent to increasing the value of the material constants which results in an increase in the speed of the waves

On love waves in a stratified hypoelastic solid with material boundary

Transverse surface waves in a half-space covered with a stratum of a different material are investigated in the context of hypoelasticity of grade zero, taking into account the surface stress effects on the boundary. It is found that the wave motion is possible and that unlike in the corresponding problem with classical boundary, the variation of amplitude in the stratum may be either periodic or exponential. When the amplitude in the stratum is periodic, the motion is similar to that in a stratum bounded on both sides by very deep layers of different elastic or hypoelastic materials. © 1977 Indian Academy of Sciences

Axisymmetric Thermoelastic Interactions without Energy Dissipation in an Unbounded Body with Cylindrical Cavity

The linear theory of thermoelasticity without energy dissipation is employed to study thermoelastic interactions in a homogeneous and isotropic unbounded body containing a cylindrical cavity. The interactions are supposed to be due to a constant step in radial stress or temperature applied to the boundary of the cavity, which is maintained at a constant temperature or zero radial stress (as the case may be). By using the Laplace transform technique, it is found that the interactions consist of two coupled waves both of which propagate with a finite speed but with no attenuation. The discontinuities that occur at the wavefronts are computed. Numerical results applicable to a copper-like material are presented

Theory of water and charged liquid bridges

The phenomena of liquid bridge formation due to an applied electric field is investigated. A new solution for the charged catenary is presented which allows to determine the static and dynamical stability conditions where charged liquid bridges are possible. The creeping height, the bridge radius and length as well as the shape of the bridge is calculated showing an asymmetric profile in agreement with observations. The flow profile is calculated from the Navier Stokes equation leading to a mean velocity which combines charge transport with neutral mass flow and which describes recent experiments on water bridges.Comment: 10 pages 12 figures, misprints corrected, assumptions more transparen

Comments on the articles "Hyperbolic thermoelasticity: A review of recent literature" (Chandrasekharaiah DS, 1998, appl mech rev 51(12), 705-729) and "Thermoelasticity with second sound: a review" (Chandrasekharaiah DS, 1986, appl mech rev 39(3), 355-376)

This review article is a continuation of a previous article by the author, Thermoelasticity with second sound: A review, which appeared in this journal in March, 1986 (Appl Mech Rev39 (3) 355-376). Here, attention is focused on papers published during the past 10-12 years. Contributions to the theory of thermoelasticity with thermal relaxation and the temperature-rate dependent thermoelasticity theory are reviewed. The recently developed theory of thermoelasticity without energy dissipation is described, and its characteristic features highlighted. A glance is made at the new thermoelasticity theory which includes the so-called dual-phase-lag effects. There are 338 references

Two different fractional Stefan problems which are convergent to the same classical Stefan problem

Two fractional Stefan problems are considered by using Riemann-Liouville and Caputo derivatives of order $\alpha \in (0,1)$ such that in the limit case ($\alpha =1$) both problems coincide with the same classical Stefan problem. For the one and the other problem, explicit solutions in terms of the Wright functions are presented. We prove that these solutions are different even though they converge, when $\alpha \nearrow 1$, to the same classical solution. This result also shows that some limits are not commutative when fractional derivatives are used.Comment: 14 pages, 1 figur

Elasticity-driven Nanoscale Texturing in Complex Electronic Materials

Finescale probes of many complex electronic materials have revealed a non-uniform nanoworld of sign-varying textures in strain, charge and magnetization, forming meandering ribbons, stripe segments or droplets. We introduce and simulate a Ginzburg-Landau model for a structural transition, with strains coupling to charge and magnetization. Charge doping acts as a local stress that deforms surrounding unit cells without generating defects. This seemingly innocuous constraint of elastic `compatibility', in fact induces crucial anisotropic long-range forces of unit-cell discrete symmetry, that interweave opposite-sign competing strains to produce polaronic elasto-magnetic textures in the composite variables. Simulations with random local doping below the solid-solid transformation temperature reveal rich multiscale texturing from induced elastic fields: nanoscale phase separation, mesoscale intrinsic inhomogeneities, textural cross-coupling to external stress and magnetic field, and temperature-dependent percolation. We describe how this composite textured polaron concept can be valuable for doped manganites, cuprates and other complex electronic materials.Comment: Preprin

Thermodynamics of volume collapse transitions in cerium and related compounds

We present a non-linear elastic model of a coherent transition with discontinuous volume change in an isotropic solid. The model reproduces the anomalous thermodynamics typical of coherent equilibrium including intrinsic hysteresis (for a pressure driven experiment) and a negative bulk modulus. The novelty of the model is that the statistical mechanics solution can be easily worked out. We find that coherency leads to an infinite-range density--density interaction, which drives classical critical behavior. The pressure width of the hysteresis loop shrinks with increasing temperature, ending at a critical point at a temperature related to the shear modulus. The bulk modulus softens with a 1/2 exponent at the transition even far from the critical point. Many well known features of the phase diagram of Ce and related systems are explained by the model.Comment: Acta Materialia, in pres