Modeling Ultrasonic Guided Wave Generation From Piezoelectric Fiber Composite Strip Actuators

Structural health monitoring (SHM) and condition based maintenance (CBM) are keys to shifting the paradigm from schedule based maintenance to cost effective operation and maintenance of reliable systems. Continuous comb transducer strips have the potential to generate ultrasonic guided waves for structural health monitoring of plate and shell structures (pipelines, pressure vessels, storage tanks, airframes). A theoretically driven approach, based on the application of wave mechanics principles, is used to research and design a network of strip sensor. Fibrous piezoelectric composites are considered for the comb elements, widely expanding the design space of these elements to include fiber orientation and volume fraction in addition to size, configuration, and location of the electrodes. Piezoelectric and mechanical properties for these innovative sensor designs are estimated through micromechanical modeling. Specifically, micromechanics enables us to consider different fiber orientations and constituent properties and provides the composite properties for input to finite element analysis of wave propagation. Finite element simulations of ultrasonic guided wave generation and propagation using Abaqus Explicit-Standard Co-Simulation are conducted in order to design the sensory system.