In this paper deflection and free vibration of sandwich panel is studied. The core of Sandwich panels is made of hexagonal honeycomb and faces are made of two different materials of Carbon Fiber Reinforced Plastic and K-aryl/epoxy covering. The governing equations are deduced from the First order Sheer Deformation Theory (FSDT) and they are solved using Generalized Differential Quadrature Method (GDQM). The classical method in the references is used to verify the DQ method and to show that the applied GDQM method has a good results with compared to the references. Deflection of sandwich panel is investigated with two different load types. Finally natural frequency for the first 4 modes and the two different faces materials are calculated and the effect of various lengths to core thickness ratios and faces to honeycomb core thickness ratios are studied. Further, the effect of foundation stiffness coefficient on deflection and natural frequency are showed Manuscript profile

In the present paper, electrical energy harvesting from random vibrations of an Euler-Bernoulli nano-beam with two piezoelectric layers is investigated. The beam is composed of an aluminum layer together with two piezoelectric ceramic layers (PZT 5A) serving as energy harvesting sensors. In the proposed method, the equations governing the bimorph nano-beam will be analytically derived using classical beam theory with corresponding modification coefficients to the nano-structure applied. Then, the derived system of equations will be solved following Kantorovich method. Assumed boundary conditions for the nano-beam are as follows: a clamped end with the mass concentrated at the free end of the beam. Further, the input activation function of the system for energy harvesting was taken as being random. Since the objective of this research is to investigate the amount of harvested energy, the section on the results provides associated voltage and maximum output power curves with the bimorph nano-beam under random activation and input white noise, while also presenting the effects of characteristics and scale factor of the nano-particles on the amount of harvested energy. Manuscript profile