The present work deals with the active vibration control of composite beam under thermal environment using finite element method. The effect of fiber orientation and temperature on natural frequency and damping of the system are investigated for different boundary conditions. The temperature-dependent properties of viscoelastic core are considered. Results are presented for frequencies and loss factor with different core material and core thickness. Characteristics of loss factor and frequency near the buckling temperature are discussed, and the effect of core thickness on buckling temperature is also investigated. © 2007 Elsevier Ltd. All rights reserved.

Raju Sethuraman

Department of Mechanical Engineering

- Sharnappa

Natrajan Ganesan

Boundary conditions

constrained optimization

Damping

finite element method

Thermal effects

Viscoelasticity

BUCKLING TEMPERATURE

CORE THICKNESS

Loss factor

Temperature-dependent properties

Composite beams and girders

IIT Madras is a public technical and research university located in Chennai, Tamil Nadu. Founded in 1959, it is recognised as an Institute of National Importance.

IIT Madras has been ranked as the top engineering institute in India for four years in a row by the National Institutional Ranking Framework of the MHRD

It currently offers undergraduate, postgraduate and research degrees across 16 disciplines in Engineering, Sciences, Humanities and Management. About 596 faculty belonging to science and engineering departments and centres of the Institute are engaged in teaching, research and industrial consultancy.

IIT Madras

Journal of Sound and Vibration

Sandwich beam having viscoelastic core is analyzed for its buckling and vibration behavior under thermal environments, using the finite element method. Variation of natural frequencies and loss factors with respect to temperature is investigated. The formulation is based on the displacement field proposed by Khatua and Cheung [International Journal for Numerical Methods in Engineering 6 (1973) 11-24]. The behavior of the beam considering both the temperature dependent and independent shear modulus of the core is studied. A parametric study is conducted with core thickness as parameter and its influence on buckling temperatures, natural frequencies and loss factors is studied. Two different core materials are considered for the analysis to find the influence of material on buckling and vibration behaviors. © 2005 Elsevier Ltd. All rights reserved.

Buckling and vibration of sandwich beams with viscoelastic core under thermal environments

AIAA Journal

Performance of Smart Damping Treatment Using Piezoelectric Fiber-Reinforced Composites

This work deals with the active vibration control of beams with smart constrained layer damping (SCLD) treatment. SCLD design consists of viscoelastic shear layer sandwiched between two layers of piezoelectric sensors and actuator. This composite SCLD when bonded to a vibrating structure acts as a smart treatment. The sensor piezoelectric layer measures the vibration response of the structure and a feedback controller is provided which regulates the axial deformation of the piezoelectric actuator (constraining layer), thereby providing adjustable and significant damping in the structure. The damping offered by SCLD treatment has two components, active action and passive action. The active action is transmitted from the piezoelectric actuator to the host structure through the viscoelastic layer. The passive action is through the shear deformation in the viscoelastic layer. The active action apart from providing direct active control also adjusts the passive action by regulating the shear deformation in the structure. The passive damping component of this design eliminates spillover, reduces power consumption, improves robustness and reliability of the system, and reduces vibration response at high-frequency ranges where active damping is difficult to implement. A beam finite element model has been developed based on Timoshenko's beam theory with partially covered SCLD. The Golla-Hughes-McTavish (GHM) method has been used to model the viscoelastic layer. The dissipation co-ordinates, defined using GHM approach, describe the frequency-dependent viscoelastic material properties. Models of PCLD and purely active systems could be obtained as a special case of SCLD. Using linear quadratic regulator (LQR) optimal control, the effects of the SCLD on vibration suppression performance and control effort requirements are investigated. The effects of the viscoelastic layer thickness and material properties on the vibration control performance are investigated.

Finite element formulation and active vibration control study on beams using smart constrained layer damping (SCLD) treatment

ACTIVE CONSTRAINED LAYER DAMPING OF CLAMPED-CLAMPED PLATE VIBRATIONS

ACTIVE CONSTRAINED LAYER DAMPING OF THIN CYLINDRICAL SHELLS

Dynamic modeling of active constrained layer damping of composite beam under thermal environment

Journal	Journal of Sound and Vibration
Publisher	Academic Press
ISSN	0022460X
Open Access	No