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Showing 1 to 14 of 14 for “"Constrained Layer damping"”.
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Using selectively placed patches of constrained layer damping to quiet home appliances
… effective locations for small pieces of constrained layer damping material ( less than 10% of the total available surface area ) that produce significant noise reductions. Work performed to reduce the noise radiation from two real structures will be described. Both structures represent …
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Evaluation of analytical and experimental methods to predict constrained layer damping behavior
Constrained layer damping (CLD) for three layer beams with viscoelastic cores and aluminum or graphite/epoxy composite laminate outer layers was investigated for model comparison, sensitivity to design parameters, and evaluation of experimental loss factor estimation techniques. Model comparison …
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Passive Viscoelastic Constrained Layer Damping Application for a Small Aircraft Landing Gear System
… small aircraft landing gear system for improved damping performance. The applied viscoelastic damping treatment to the gear was of a constrained layer type, promoting increased shear deformation over free surface treatments, and therefore enhanced energy dissipation within the viscoelastic layer. …
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Enhancement of the Dynamic Buckling Load and Analysis of Active Constrained Layer Damping with Extension and Shear Mode Piezoceramic Actuators
… plate sandwiched between two piezoceramic (PZT) layers. Points on the four edges of the bottom surface of the plate are restrained from moving vertically. The two opposite edges of the plate are loaded by equal in-plane compressive loads that increase linearly with time and the other two edges …
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Hybrid Active/Passive Models with Frequency Dependent Damping
To add damping to structures, viscoelastic materials (VEM) are added to structures. In order to enhance the damping effect of the VEM, a constraining layer is attached, creating a passive constrained layer damping treatment (PCLD). When this constraining layer is an active element, the treatment is …
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Structural elements with mathematically defined surfaces for enhanced structural and acoustic performance
… the two-dimensionally curved designs with constrained layer damping is also investigated. Further, it is also the goal of this research that these panels can be inexpensively manufactured with current manufacturing methods (e.g. stamping, rolling, thermoforming, etc.), resulting in a more …
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A Distributed Active Vibration Absorber (DAVA) for Active-Passive Vibration and Sound Radiation Control
… material polyvinylidene fluoride (PVDF) and thin layers of lead. The tested device is designed to weight less than 10% of the main structure and has a resonance frequency around 1000 Hz. Experiments have been conducted on a simply supported steal beam (24"x2"x1/4"). Preliminary results show that …
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A theoretical and experimental study of modal interactions in metallic and laminated composite plates
… supported plate with and without a constrained-layer damping (CLD) patch attached on its upper left-hand side surface. The natural frequencies and mode shapes were used to ascertain the effect of the CLD patch.
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Internal Variable and Temperature Modeling Behavior of Viscoelastic Structures -- A Control Analysis
… of the methodologies dealing with viscoelastic damping focused exclusively on the frequency dependence behavior of the material. Only a few looked into the temperature dependence of the model, although none of them has taken a more serious investigation on the control design subjected to …
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An Experimental Evaluation of the Application of Smart Damping Materials for Reducing Structural Noise and Vibrations
This study evaluates the application of smart damping materials for reducing structural noise and vibrations. The primary purposes of this study are to: 1. Explore the feasibility of smart damping materials, such as piezoelectric materials, for augmenting and improving the noise and vibration …
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Passive Damping in Stiffened Structures Using Viscoelastic Polymers
… unwanted vibrations from a system is passive damping, by using a viscoelastic material. This dissertation will primarily focus on constrained layer passive damping treatments in structures and the investigation of associated complex modes. The key idea behind constrained damping treatment is …