THE ANALYSIS OF FEM RESULTS CONVERGENCE IN MODELLING PIEZOELECTRIC ACTIVE SHELL STRUCTURES

Sa？etak The field of active/adaptive structures has been the subject of intense interest over the past couple of decades. The progress in this research field strongly depends on the availability of adequate and reliable modelling tools. Regarding structural analysis in general, the finite element method (FEM) has imposed itself as the method of choice for modelling and simulation. Piezoelectric active structures are characterized by strong enough coupling between the mechanical field and the electric field, which is further used for the realization of active structural behaviour. The descriptions of the mechanical and electrical field as well as their coupling significantly affect the convergence of the FEM results with mesh refinement, which may proceed in a trend different to what is commonly expected when FEM is applied to purely mechanical problems. The paper considers this aspect by using two quadratic shell type finite elements developed for modelling piezoelectric composite laminates. Both full and uniformly reduced integration techniques are taken into consideration in a set of examples involving composite laminates with active piezoelectric layers