Active control of laminated composite plates using smart symmetric and antisymmetric macro fiber composite patches

This paper deals with the development of a novel hybrid-Trefftz finite element (HTFE) model of smart laminated composite plates for investigating the performances of symmetric and antisymmetric piezoelectric patches acting as the distributed actuators. The patches are made of d31 type macro fiber composite (MFC) piezoelectric layers while the volume and thickness of all patches are same. The substrates of these smart plates include thin symmetric cross-ply and antisymmetric cross-ply and angle-ply plates. The Trefftz functions of the HTFE are constructed in a straightforward manner from the finite number of free-field exact solutions of the homogeneous simultaneous governing partial differential equations (PDEs) of the element domain. The frequency response functions of the plates computed by the derived HTFE model have been compared with that obtained by the conventional finite element model. Excellent matching of the responses derived by the two models has been observed. The present study reveals that the antisymmetric piezoelectric patches perform significantly better than the symmetric piezoelectric patches. It is also explored that the patch with rectangular plan form performs better than the patch with trapezoidal plan form.