Enclosure Acoustics Modeling and Control Utilizing a Passive and Active Structural Tailoring

Abstract

The subject of this paper is the redesign a flat panel to couple less effectively to acoustic enclosures, and improve transmission loss between the enclosures. First presented is a brief background of the theory of acoustic noise in reverberant enclosures. Finite dimensional acoustic and structural models are linked producing a fully coupled linear control design model. These developments are then specifically applied to a 3-D acoustic chamber consisting of two separated 4ft x 4ft x 8ft enclosures. Passive redesign of the structure for minimal coupling and several mass mimicking active noise controllers were investigated. A decentralized MIMO controller was designed and simulated to mimic the effect of additional mass. These models and designs are currently being validated on an experimental test bed. Future efforts will examine additional control design strategies including modal clustering, passification by optimal blending of sensors and actuators, and the use of locally reacting sources on the plate surface to target acoustic structure coupling directly.

Active control of vehicle’s interior sound field by using multichannel H∞ robust controller

“…In equation ( 14), c is the velocity of sound in the fluid and V a is the acoustic modal mass matrix. 12 The equations above can be represented in a statespace form with 2 3 (k + m) of the state variables (m is the number of the structural modes and k is the number of the acoustic modes). Theoretically, the values of m and k must be infinite.…”

“…In equation (14), c is the velocity of sound in the fluid and V a is the acoustic modal mass matrix. 12…”