Active control of harmonic sound transmission into an acoustic enclosure using both structural and acoustic actuators

Abstract

This paper describes an analytical and experimental investigation into the active control of harmonic sound transmission in a structural-acoustic coupled system. A rectangular enclosure is considered that has five acoustically rigid walls and a flexible plate on the remaining side through which a harmonic sound wave is transmitted into the enclosure. The control system is designed to globally reduce the sound field inside the enclosure, and the roles of structural and acoustic actuators are of particular interest. Three control configurations, classified by the type of actuators, are compared and discussed. They are: (i) use of a single point-force actuator, (ii) use of a single acoustic piston source, and (iii) simultaneous use of both a point-force actuator and an acoustic piston source. It is shown both analytically and experimentally that the point-force actuator is effective in controlling plate-dominated modes while the acoustic source is effective in controlling cavity-dominated modes. Since the transmitted sound field is governed by both plate- and cavity-dominated modes, the hybrid use of both types of actuators is shown to be a desirable configuration for the active control of sound transmission into a structural-acoustic coupled system.

Control strategies and mechanisms for active control of sound transmission into a vibro-acoustic enclosure

“…Unexpected noise is often transmitted and radiated through these flexible boundaries into the interior cabin. Active noise and vibration control (ANVC) has been proven to be an efficient technique to control sound transmission (Pan and Hansen, 1990;Qiu, 1995;Banks, 1994;Koshigoe and Teagle, 1995;Koshigoe and Murdock, 1993b;Kim and Brennan, 2000;Al-Bassyiouni and Balachandran, 2005;Jin et al, 2009aJin et al, , 2009bJin et al, , 2009cLau and Tang, 2003;Tanak and Kobayashi, 2006;Kaizuka and Tanaka, 2007;Sun and Zhao, 2010). In analytical studies of active sound transmission control in such vibro-acoustic system, a rectangular cavity model with five rigid walls and one flexible thin plate cover was most frequently discussed, and has been of interest to many investigators with the aim of achieving physical insight so that an effective control system can be designed.…”

“…Banks (1994) and Koshigoe et al (1993bKoshigoe et al ( , 1995 also investigated the transmission of sound from an external source into a cavity and their controls, and Green's functions were used to model the equations for structural-acoustic coupling interaction. Kim and Brennan (2000) presented a theoretical and experimental investigation into the active control of sound transmission into a structural-acoustic coupled system using both structural and acoustic actuators, and the theoretical formulation was given using the impedance-mobility approach. Jin et al (2009b) presented a theoretical investigation on active control of sound transmission into a structural-acoustic coupled system using the radiation modes control approach.…”

Active Control of Sound Transmission Through Windows With Carbon Nanotube-Based Transparent Actuators

“…One approach that has been investigated by other researchers is to place loudspeakers on the sides of the cavity of double-glazed windows as secondary sources [2]- [4]. However, this cavity control approach is not effective in controlling panel radiation-dominated sound [5]. The other approach is to use a small voice-coil actuator to vibrate the glass panel itself to generate the canceling sound [6].…”

Virtual sensors for active noise control in acoustic–structural coupled enclosures using structural sensing: Robust virtual sensor design

“…Part of the work focused on active control of structural sound radiation to a free field, while other on acoustic-structural coupled enclosures (such as Pan and Hansen, 1991;Snyder and Tanaka, 1993;Cazzolato, 1999;Kim and Brennan, 2000;Tanaka and Kobayashi, 2006;Hill et al, 2009;Li and Cheng, 2010 and references therein). Two active control strategies in this aspect are the global and local active controls, showing respective merits and limitations.…”