Specialty Finite Elementsvibration 4 small

Our coupled mixed-field mechanics models for piezocomposite laminates were extended to include non-linear effects arising due to large displacements & rotations. This has resulted in the development of a novel non-linear piezolaminate theory, a series of non linear finite-element formulations for active/sensory piezocomposite structures, and a new 8-node finite element, which all together have yielded unprecedented new analytical capabilities, some of them are enumerated below:

  1. Electro-Mechanical Initial Buckling Analysis of Active Structures
    • Prediction of Piezoelectric Buckling. The linear buckling of adaptive piezocomposite structures can be formally predicted. Typical predictions of the first buckling shape of a simply-supported composite plate induced by in-plane actuator loading is shown in the figure.
    • Active Mechanical Buckling Compensation. The FE has also illustrated the possibility to actively hider/compensate mechanical buckling in active structures and enable formal predictions of required actuator loading.
    • Related Publication(s): Varelis D. and Saravanos D. A. "Nonlinear Coupled Mechanics and Buckling Analysis of Composite Plates with Piezoelectric Actuators and Sensors," Smart Materials and Structures, Vol. 11, No. 3, Jun. 2002, pp. 330-336.
  2. Non-linear Response of Active Structures
    • Nonlinear Mechanics. Additional non-linear mechanics formulations and FE models have enable detailed predictions of the progressively increasing non-linear behavior of active plate structures undergoing severe actuator and/or mechanical loading. Typical non-linear predictions of the transverse deflection of an active plate due to a "bending" electric potential pattern applied at PZT-5 actuators, is shown in the figure.
    • Related Publication(s): Varelis D. and Saravanos D. A., "Coupled Finite Element For The Non-linear Response of Laminated Piezoelectric Composite Structures", AIAA paper 2002-1442, 43rd AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference - 10th Adaptive Structures Conference, Denver, Colorado, April 22-25, 2002.
  3. Buckling and Postbuckling of Active Structures
    • Buckling Investigations. The capability of the nonlinear coupled mechanics and FE to simulate the prebuckling and postbuckling behavior of active structures subject to in-plane actuator and mechanical loads. An example of predicted pre- and post-buckling transverse deflection path in an active plate due to "compressive" electric potentials applied at the PZT-5 actuators is shown in the figure.
    • Related Publication(s): Varelis D. and Saravanos D. A., "Non-linear Mechanics for Piezoelectric Composite Plates with Applications to Buckling and Postbuckling Behavior," Proceedings, 13th International Conference on Adaptive Structures and Technologies, CRC Press, Potsdam, Germany, Oct. 7-10, 2002
  4. Other Related Activities
    • Coupled shear-layerwise Shell FE
    • Coupled Layerwise Plate FEs
    • Multi-Field (thermo-piezo-composite) 8-node Shell FE

Mesomechanics Models for Piezo-Composite Laminates
Some examples include:

  • Coupled Mixed-Field (single layer - layerwise) Piezoelectric Laminate Theory
  • Coupled Fully Layerwise Laminate models
  • Laminate Theories with Thermo-Piezoelectric Effects
  • Non-linear Piezolaminate Mechanics for Large Displacements
  • Cylindrical & Shell Laminate Configurations

Applications

  • Integrated Damping Models (micromechanics, ply, laminate) for Polymer Matrix Composite Laminates
  • Layerwise Models for Laminates with Constrained Damping Layers, Sandwiched Foam Cores
  • Multi-Damped Composite Laminates with Shunted Piezoelectics