Magnetoelastic plane waves in rotating media in thermoelasticity of type II (G-N model)

A study is made of the propagation of time-harmonic plane waves in an infinite, conducting, thermoelastic solid permeated by a uniform primary external magnetic field when the entire medium is rotating with a uniform angular velocity. The thermoelasticity theory of type II (G-N model) (1993) is used to study the propagation of waves. A more general dispersion equation is derived to determine the effects of rotation, thermal parameters, characteristic of the medium, and the external magnetic field. If the primary magnetic field has a transverse component, it is observed that the longitudinal and transverse motions are linked together. For low frequency ( χ ≪ 1 , χ being the ratio of the wave frequency to some standard frequency ω ∗ ), the rotation and the thermal field have no effect on the phase velocity to the first order of χ and then this corresponds to only one slow wave influenced by the electromagnetic field only. But to the second order of χ , the phase velocity, attenuation coefficient, and the specific energy loss are affected by rotation and depend on the thermal parameters c T , c T being the nondimensional thermal wave speed of G-N theory, and the thermoelastic coupling ε T , the electromagnetic parameters ε H , and the transverse magnetic field R H . Also for large frequency, rotation and thermal field have no effect on the phase velocity, which is independent of primary magnetic field to the first order of ( 1 / χ ) ( χ ≫ 1 ), and the specific energy loss is a constant, independent of any field parameter. However, to the second order of ( 1 / χ ), rotation does exert influence on both the phase velocity and the attenuation factor, and the specific energy loss is affected by rotation and depends on the thermal parameters c T and ε T , electromagnetic parameter ε H , and the transverse magnetic field R H , whereas the specific energy loss is independent of any field parameters to the first order of ( 1 / χ ).