title: Design of ultrasonic array elements for acoustic power considerations.
abstract: In sound-transmitting applications such as therapeutic ultrasound, the acoustic power at a particular operating frequency is a critical figure of merit for transducer/array design. A design methodology for enhancing the acoustic power radiated from fluid-loaded piezoelectric array elements at a fixed frequency is developed in this paper. A gradient-based optimization algorithm is integrated within the finite element framework to guide the determination of the two design variables, the piezoelectric element thickness and the matching layer thickness, to optimize the acoustic power output. A method for avoiding explicit remeshing in the optimization iteration is presented. Optimized designs are determined numerically, and the effectiveness of the design method is confirmed by experimental measurements. The validated numerical analysis also shows that conventional design strategies using one-dimensional transducer analysis and rule-of-thumb matching layer or protection layer sizing rules may not give the best design for array elements in acoustic power applications.
authors.affiliation: Department of Mechanical Engineering and Applied Mechanics, University of Michigan, Ann Arbor 48109-2125, USA.
authors.forename: Yuan
authors.initials: Y
authors.lastname: Lin
authors.forename: Karl
authors.initials: K
authors.lastname: Grosh
mesh_terms: D000162:Acoustics; D000465:Algorithms; D004867:Equipment Design; D020342:Finite Element Analysis; D014464:Ultrasonic Therapy / Q000295:instrumentation*