2020 Volume 2020 Pages 20200015
Piezoelectric bimorphs in actuator and sensor applications are usually connected to an external circuit. The mechanical behavior of the piezoelectric bimorph is affected by charge from the circuit, and it behaves as a kind of capacitor in the circuit. Therefore, the interaction between the electrical circuit and piezoelectric bimorph forms the multiphysics inverse piezoelectric – direct piezoelectric – circuit interaction problem. This multiphysics coupling should be taken into account in the design process of the actuators and sensors using the piezoelectric bimorph. Here, the novel finite element analysis method is proposed for this inverse piezoelectric - piezoelectric - circuit coupled problem. The inverse piezoelectric and direct piezoelectric analyses are performed using the finite element method with the shell and solid elements, respectively, in order to consider the thin composite structure. Therefore, the transformation method between the solid and shell variables are used. The description of the circuit is a single degree of freedom. The coupled equations for the direct piezoelectric – circuit interaction are proposed from the continuous conditions for the electric potential and the charge. The coupled algorithm is based on the block Gauss-Seidel method. In the inverse piezoelectric analysis, the homogenization method about the bending rigidity and the mass is used. In the direct piezoelectric analysis, the pseudo-piezoelectric evaluation method for the conductor is used. Finally, it is demonstrated that the proposed method can analyze the coupling phenomena in the RC circuit and the shunt damping application accurately.
