TITLE:
Acoustic Modeling of a 3-Layered Panel Incorporating Electro-Rheological/ Magneto-Rheological (EMR) Fluids
AUTHORS:
Nader Mohammadi
KEYWORDS:
ER/MR Fluid; Multi-Layers Panel; Transmission Loss
JOURNAL NAME:
Open Journal of Acoustics,
Vol.4 No.1,
March
13,
2014
ABSTRACT: Applications of Electro-Rheological (ER) or Magneto-Rheological (MR) fluids as typical smart materials have been widely investigated over the past decades (since their
introduction in 40’s). The special applications of these materials as a means of noise suppression are not yet investigated. Constrained Layer Damping (CLD) sheets can be
realized by incorporating EMR (ER/MR) materials. In this way, a multilayered damping sheet is obtained with
adaptive (tunable) stiffness and damping characteristics. These
properties are easily changed in proportion to the electric (magnetic) field applied
upon the EMR layer. This notion has been introduced for semi-active
vibration control problems. Herein, such panels incorporating EMR material are proposed for adaptive acoustic treatments. Modeling (simulation) of a 3-layered panel with the middle layer being
EMR with adjustable properties is carried out in this
paper. The tunability of transmission/absorption characteristics of these composite sheets enables us making smart panels for adaptive noise and acoustic treatments. An adaptive
performance can be achieved via changing the properties of such panels, on
line, according to some sensor outputs. The main objective is to develop proper
models to predict the Transmission Loss (TL) of such panels.
Also, the TL of this panel is compared with the middle layer of a Newtonian
fluid.