Adaptive vibration control through a SMA embedded panel

Dynamic behavior of structural elements and their performance in terms of noise and vibration control may be remarkably affected by several parameters, like geometry, material properties, stress field, etc. Ability of adaptively controlling one or more of these parameters leads to a structure fitting different requirements in several working conditions. Research activities presented in this work are focused on the design of a fiber-glass laminate structural element with SMA wires embedded along the widest dimension. SMA contraction by the Joule effect heat adduction leads, if suitably constrained on the edges, to an internal stress field with a consequent over-all stiffness increase. The finite element code MSC.NASTRAN is used to simulate the whole system made of a plate and SMA wires controlling elements. The behavior of the SMA is modeled through the NASTRAN card CELAS that allows one to consider the additional SMA activation stiffness with a suitable "spring" cons tant, depending on the wire temperature and a suitable discretization parameter. The finite difference model of the SMA is achieved and integrated in the FEM solver.