On Generalized Magneto-thermoelastic Rayleigh Waves in a Granular Medium Under the Influence of a Gravity Field and Initial Stress

• Published in: Journal of vibration and control Vol. 17; no. 1; pp. 115 - 128
• Main Authors: Abd-Alla, A.M., Abo-Dahab, S.M., Hammad, H.A., Mahmoud, S.R.
• Format: Journal Article
• Language: English
• Published: London, England SAGE Publications 01-01-2011; SAGE PUBLICATIONS, INC
• Subjects: Coefficient of friction; Friction; Gravitation; Gravitational fields; Initial stresses; Magnetic fields; Mathematical analysis; Rayleigh waves; Relaxation time; Satellites; Stress; Stress propagation; Stress relaxation; Thermal stress; Velocity; Vibration; Wave propagation; Wave velocity; Granular medium; gravity field; relaxation times; initial stress; rayleigh waves; magneto-thermoelastic waves
• ISSN: 1077-5463; 1741-2986
• DOI: 10.1177/1077546309341145

In this paper, the influence of magnetic field, gravity field and initial stress on Rayleigh waves propagation in a granular medium under incremental thermal stresses and relaxation times is studied. The frequency equation of Rayleigh waves is obtained in the form of a determinant containing a term involving the coefficient of friction of a granular medium. Some special cases are obtained from this study. Analytically, from the results obtained, one may illustrate that the effect of relaxation times, gravity field, initial stress and magnetic field on Rayleigh wave velocity are very pronounced. It is found that the frequency equation of Rayleigh waves changes with respect to this friction. When the medium is an orthotropic and the magnetic field and friction coefficient vanish, the derived frequency equation reduces to that obtained by Abd-Alla and Ahmed. Relevant results from previous investigations are deduced as special cases of this study.