Vibration Suppression of an Elastic Plate by Use of an Electrorheological Patch and Constraining Layer

Electrorheological materials are a class of smart materials which exhibit dramatic changes in mechanical properties (like shear modulus) due tostrong applied external electric fields. In this paper free and forced harmonic vibration of a rectangular elastic plate with a rectangular ER patch with arbitrary size and location on the plate and a constraining layer on the patch is investigated. Like most of the papers on the usage of ER materials in adaptive structures, this paper considers the ER material as a viscoelastic material, and complex modulus is used to identify the shear properties of the material in harmonic oscillation. A dynamic model for the electric field-dependent steady-state vibrational response of a rectangular plate and the ER patch and it’s constraining layer, subjected to a general harmonic transverse excitation, is developed. Hamilton’s principle and the classical thin plate theory are applied to derive a set of fully coupled dynamic equations of motion along with the associated general boundary conditions. Assuming simply-supported edge conditions, for the base plate, the displacement components of the plate arepostulated by means of generalized double Fourier series with frequency-dependent coefficients. The natural frequencies are subsequently determined.The contribution of this work to the previous works, which have investigated the vibration of ER based full sandwich plates, is it’s more general and extended approach. Of course this approach is of more interest in industrial applications. In fact previous papers can be regarded as a special case of the present work. The results are validated with the results of [Hasheminejad and Maleki, 2009] in which vibration of the full ER based sandwich plate is formulated.

کلیدواژه ها:

Smart structures ، Electrorheological ، Semi active control ، ER patch ، vibration suppression ،