Theoretical and experimental investigations have been made to study the damping effectiveness of unconstrained partially applied damping treatments applied to rectangular plates. By using the finite element approach, different configurations of partially applied damping layer treatments have been analyzed for their effectiveness in realizing maximum system damping with minimum mass of the applied damping material. The effects of partial application on the modal frequencies, loss factors and mode shapes are discussed. The theoretical results are validated by suitable experiments. Specific recommendations are made for the near-optimum distribution of the damping material on the panel surface which is effective for many modes of panel response. © 1985 Academic Press Inc. (London) Limited.

Natrajan Ganesan

STRUCTURAL ANALYSIS - Mathematical Models

LAYER DAMPING

LOSS FACTORS

MODAL FREQUENCIES

Mode shapes

Rectangular plates

Plates

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IIT Madras

Partial coverage of rectangular plates by unconstrained layer damping treatments

Journal of Sound and Vibration

The plates under study are treated with an unconstrained damping layer which is applied either partially or throughout the plates. Several configurations of partial damping layer treatment has been studied and in all the cases the volume of the damping material has been kept the same. When such a plate is subjected to a harmonic excitation at one of the resonating frequencies the magnitude of the amplitude of vibration and the dynamic stresses developed in the plate will depend mainly on the damping ratio. The stresses in the damping layer depend on the damping ratio and at the same time also on the thickness of the layer. Three boundary conditions are considered and the force of excitation is of a point harmonic type. The analysis is carried out for first two modes of vibration. © 1993.

Computers and Structures

Dynamic studies on plates with unconstrained layer treatment

For theoretical evaluation of the response of a structure under random acoustic excitation a complete understanding is required of the various modes of vibration and the modal damping associated with each mode. In order to evaluate these parameters for plates with unconstrained layer damping treatment, some of the theoretical approaches applicable are used. Experimentally observed modal frequencies and associated loss factors are compared with those estimated by different theories for all edges simply supported and all edges clamped boundaries, after accounting for the damping at supports. The modes of vibration used in the theoretical analysis for these boundaries are compared with those observed in the experiments. These results are made use of in Part II for the evaluation of response under random acoustic excitation. © 1980.

Response of plates with unconstrained layer damping treatment to random acoustic excitation, part I: Damping and frequency evaluations

Journal of Engineering for Industry

The Damping Effects of Viscoelastic Materials: Part 2—Transverse Vibrations of Plates With Viscoelastic Coatings

Vibration of metal plates covered with vibration damping layers

American Documentation

4/64-00 Information storage and retrieval: A survey. 1963. George W. Barnard and Carl Abbott. Biomedical Laboratory, 6570th Aerospace Medical Research Laboratories, Aerospace Medical Division, Air Force Systems Command (Technical Documentary Rept. No. AMRL-TDR-63-8), Wright-Patterson Air Force Base, Ohio. 15 pp. $.75

Journal	Journal of Sound and Vibration
ISSN	0022460X
Open Access	No