A theoretical study of structural acoustic silencers for hydraulic systems.
Theoretical studies show that the introduction of an in-line structural acoustic silencer into a hydraulic system can achieve broadband quieting (i.e., high transmission loss). Strategies for using structural acoustic filters for simultaneously reducing reflection and transmission by tailoring the material properties are studied. A structural acoustic silencer consists of a flexible layer inserted into nominally rigid hydraulic piping. Transmission loss is achieved by two mechanisms--reflection of energy due to an impedance mismatch, and coupling of the incoming acoustic fluctuations to structural vibrations thereby allowing for the extraction of energy through losses in the structure. Structural acoustic finite element simulations are used to determine the transmission loss and evaluate designs. Results based on the interaction of orthotropic and isotropic plates with variable geometry, operating in heavy fluids like water and oil, are presented.
Ramamoorthy
Sripriya
S
Department of Mechanical Engineering, University of Michigan, Ann Arbor 48109-2125, USA.
Grosh
Karl
K
Dodson
John M
JM
D000162:Acoustics; D008962:Models, Theoretical; D009622:Noise; D014732:Vibration