Numerical analysis of natural frequencies of three-layer plate under temperature load

One of the options for controlling the dynamic state of thin-walled structures is the creation of prestress state within. Stress field can be induced by various actuators, smart materials or plastic deformation. Deformations arising from uneven temperature distribution, different coefficient of thermal expansion of the materials or boundary conditions also affect the natural frequencies. This can lead to undesirable phenomena such as loss of stability or spectrum moving into the region of frequencies subject to resonance. In this paper, the influence of temperature loading on the natural frequencies of a three-layer plate is investigated by the finite element method. The obtained solution of the spectral problem is compared with the results of other authors. Plates with different configurations and boundary conditions are considered. The relative change of the plate first three natural frequencies on temperature load are received. It is shown that the resulting prestressed state has poor effect on natural frequencies free-edges plate. The results of numerical calculations for a plate clamped on both sides demonstrate that with increasing stiffness, the critical temperatures also increase.