FORCED VIBRATIONS DUE TO MECHANICAL LOADS IN PIEZOTHERMOELASTIC HALF-SPACE

摘要

The article studies disturbances in a homogeneous, transversely isotropic, generalized piezothermoelastic half-space due to impact/continuous strip mechanical loads acting on a thermally insulated/isothermal and electrically shorted (closed circuit) surface. Combinations of the Laplace transform with respect to time and Fourier transform with respect to a space variable are employed to solve the boundary value problem in the transformed domain, in the context of classical and non-classical theories of thermoelasticity. The systems of equations are solved by using the Gauss elimination process for the unknowns. The values of these unknowns are used in the formal solution which leads to the expressions of displacements, temperature change, electric potential, electric displacement and stresses in the transformed domain. In order to obtain solution in the physical domain the inverse transform integrals are evaluated by using the Romberg integration and Fourier series approximations numerically. Temperature change, stresses and electric displacement so obtained in the physical domain, are computed numerically from the relevant expressions and relations for PZT-5A material. The illustrations and comparisons of the results for classical and non-classical theories of thermoelasticity are presented graphically. This may find applications in buzzers inside pagers and cell phones, shakers inside ultrasonic cleaners and strain sensors inside pressure gages.