Time-Dependent Creep Response of Magneto-Electro-Elastic Rotating Disc in Thermal and Humid Environmental Condition

Abstract

The aim of this paper is to analyze the time-dependent stress redistribution of a rotating magneto-electro-elastic disc. The disc is supposed to be placed in an axisymmetric temperature and moisture fields. Besides, the disc is under a centrifugal body force, an induced electric potential in addition to magnetic potential. Using equilibrium, electrostatic and magnetostatic equations, straindisplacement and stress-strain relations together with hygrothermal equations, a differential equation is obtained in which there are creep strains. Primarily, disregarding the creep strain, an analytical solution for the initial stresses, electromagnetic potentials and displacement is developed. Then, using Prandtl- Reuss relations, creep stress rates and electromagnetic potentials rates are obtained. Finally, the history of stresses, electric and magnetic potentials is obtained iteratively. In the numerical section, the influence of creep evolution, hygrothermal environmental condition, angular velocity and temperature- and moisture-dependency of elastic coefficients on the behavior of magneto-electro-elastic disc is analyzed comprehensively. The results show that the effect of hygrothermal loading and angular velocity becomes less significant after creep evolution. Also, the results imply that analysis of the effect of temperature- and moisture- dependence after creep evolution must be considered in the design progress. Besides, to avoid cracking, increasing in the tensile hoop stress at the internal surface with increasing in hygrothermal loading must be considered in design progress..