Constrained-layer damping

About: Constrained-layer damping is a research topic. Over the lifetime, 795 publications have been published within this topic receiving 15758 citations.

Smart damping of geometrically nonlinear vibrations of laminated composite beams using vertically reinforced 1–3 piezoelectric composites

Abstract: This paper deals with the analysis of active constrained layer damping (ACLD) of geometrically nonlinear transient vibrations of laminated composite beams using vertically reinforced 1–3 piezoelectric composite material as the material of the constraining layer of the ACLD treatment. A nonlinear finite element model has been developed for analyzing the ACLD of laminated symmetric and antisymmetric cross-ply and angle-ply composite beams integrated with such ACLD treatment. The von Karman-type nonlinear strain–displacement relations and the first-order shear deformation theory are used for deriving this coupled electromechanical nonlinear finite element model. The Golla–Hughes–McTavish (GHM) method has been used to model the constrained viscoelastic layer of the ACLD treatment in the time domain. The backbone curves of such a class of nonlinear systems are plotted to determine the excitation levels for causing geometrical nonlinearity. The numerical results reveal that the ACLD treatment significantly improves the damping characteristics of the cross-ply and antisymmetric angle-ply beams for suppressing the geometrically nonlinear transient vibrations of the beams.

Bending and torsional vibration control of composite beams through intelligent constrained-layer damping treatments

Abstract: This paper aims to develop a mathematical model to predict whether or not intelligent constrained-layer (ICL) damping treatments could simultaneously reduce bending and torsional vibrations of composite beams having bending-torsion coupling stiffness. The ICL composite-beam model is obtained by integrating the existing ICL composite-plate model proposed by Shen (1994). When the plate width (along the x-axis) is much smaller than the plate length (along the y-axis), integration of the ICL composite-plate equations and linearization of displacement fields with respect to x will lead to a set of equations that couple bending, torsional, and axial vibrations of a composite beam. The equations of motion and associated boundary conditions are normalized and rearranged in a state-space matrix form, and the vibration response is predicted through the transfer function approach developed by Yang-Tan (1992). A numerical example is illustrated on a composite beam with bending-torsion coupling stiffness.

Active constrained layer damping of plate vibrations: a numerical and experimental study of modal controllers

Abstract: In this paper the authors address the problem of suppressing the vibrations of a clamped-clamped plate using an active constrained layer damping treatment. This treatment involves adding viscoelastic and metallic constraining layers to the host plate and then augmenting this arrangement with an active feedback scheme using piezoelectric actuators. The basis of the control strategy is an effective model of the plate together with the passive damping treatment. The paper summarizes the modelling procedures including the finite-element formulation, model reduction and model updating. By this means a low-order model, capable of accounting for the observed behaviour, is developed. Emphasis is placed upon the design and implementation of active modal controllers based upon the reduced and updated model. Four actuator/sensor configurations are examined in both numerical and experimental studies. It is shown that effective control of the first two modes of vibration (bending and torsion) can be achieved using only a single actuator and single sensor. However, the most effective configuration involves two actuators and two sensors operating as two independent control channels. It is shown that through suitable design, the active constrained layer damping treatment is capable of avoiding problems due to spillover effects.

Active damping of geometrically nonlinear vibrations of laminated composite plates using vertically reinforced 1-3 piezoelectric composites

Abstract: This paper addresses the analysis of active constrained layer damping (ACLD) of geometrically nonlinear transient vibrations of laminated composite plates using vertically reinforced 1-3 piezoelectric composite (PZC) as the material of the constraining layer of the ACLD treatment. The Von Karman type nonlinear strain-displacement relations and the first-order shear deformation theory (FSDT) are used for deriving the coupled electromechanical nonlinear finite element model. The Golla–Hughes–McTavish (GHM) method has been used to model the constrained viscoelastic layer of the ACLD treatment in the time domain. The numerical results indicate that the ACLD patches significantly improve the damping characteristics of the cross-ply and antisymmetric angle-ply plates for suppressing the geometrically nonlinear transient vibrations of the plates.

Topology Optimization of Passive Constrained Layer Damping with Partial Coverage on Plate

Abstract: The potential of using topology optimization as a tool to optimize the passive constrained layer damping (PCLD) layouts with partial coverage on flat plates is investigated. The objective function is defined as a combination of several modal loss factors solved by finite element-modal strain energy (FE-MSE) method. An interface finite element is introduced to modeling the viscoelastic core of PCLD patch to save the computational space and time in the optimization procedure. Solid isotropic material with penalization (SIMP) method is used as the material interpolation scheme and the parameters are well selected to avoid local pseudo modes. Then, the method of moving asymptote (MMA) is employed as an optimizer to search the optimal topologies of PCLD patch on plates. Applications of two flat plates with different shapes have been applied to demonstrate the validation of the proposed approach. The results show that the objective function is in a steady convergence process and the damping effect of the plates can be enhanced by the optimized PCLD layouts.