Dynamic response of an array of flexural plates in acoustic medium

Abstract

The dynamic response of a transducer array made up of circular flexural plates in immersion is analytically calculated. The calculation method includes three steps: (1) the calculation of parallel resonant frequency and the velocity profile of each plate, (2) the calculation of mutual acoustic impedance between the plates, and (3) the calculation of velocity response, including the mechanical and acoustic impedance. The calculation method is validated by both finite element analysis and measurement results of a fabricated capacitive micromachined ultrasonic transducer. Based on the calculated velocity, the near-field pressure and the near-to-far field radiation patterns are presented. The flexural plate array in immersion displays two modes of operation. At low frequency, the mode shape of the transducer array is similar to that of a suspended plate and, at certain frequencies, two groups of plates move in opposite phase, which results in the cancellation of the average velocity. At high frequency, the mode shape is similar to that of a piston transducer; however, the near-field pressure distribution is similar to that of a resilient disk.

A fluid-coupled transmitting CMUT operated in collapse mode: Semi-analytic modeling and experiments

“…Similarly, on a larger scale in the case of multiple CMUT cells, the acoustic pressure radiation of one cell is affected by other cells in the array [28]. This interaction between cells is commonly referred to as mutual radiation [16].…”

Total Acoustic Power of Two Concentric Clamped Circular Plates Vibrating in a Fluid

“…Majority of studies dealt with sound radiation of a single vibrating surface such as a piston, membrane, plate, or shell, where the fluid loading influences considerably responses of vibrating structures. Literature studies can be divided into three major groups dealing with sound radiation of a single surface source , a system of two or more surface sources [31][32][33][34][35][36][37][38][39][40][41], and systems of active control of noise and vibrations [42][43][44][45][46][47][48][49][50][51][52][53][54].…”