Traveling Wave Phenomenon Through Piezoelectric Actuation of a Free-Free Cylindrical Tube

Previous work has demonstrated that piezoceramics are capable of generating net wave propagation without reflections in one-dimensional structures. The investigation into cylindrical traveling waves provides insight into unique dynamics (i.e., symmetric and non-symmetric modes) that have yet to be fully defined for two and three dimensional systems. The work herein will focus on the generation and characterization of traveling waves that propagate along the circumferential direction. The coupled system, given by a free-free cylinder with multiple piezoelectric actuator (PZT) patches, is used to evaluate several traveling wave modes in the cylinder. The use of structurally integrated piezoelectric patches as actuators has many advantages over the conventional shakers. Apart from the small, low weight, low cost and the size of these ceramic plates, PZTs can also generate waves over a wide frequency range. The use of multiple PZTs can be leveraged to excite the systems at a given frequency with a defined phase difference between them in order to generate highly controlled directional traveling waves in the cylindrical structure without reflections. Finite Element Modeling (FEM), in conjunction with experiments, were conducted to provide a comprehensive understanding of the generation and propagation behavior of the traveling wave modes in a thin walled cylinder.