Abstract
A beam partially covered with a constrained damping layer is analyzed. The longitudinal normal strain and shear strain in the viscoelastic layer are considered. Hamilton's principle is used to derive equations of motion and boundary conditions. A sixth-order equation is used to describe the portion of the beam covered with a constrained damping layer. The characteristic equations are solved numerically to determine normalized natural frequency and loss factor values. The loss parameter (normalized loss factor) is shown to be a function of the shear parameter gT; the geometric parameter YT; the normalized coverage length LC/L; dimensionless coefficients B 1,B2, and B3; and the core loss factor η2. It is shown that traditional constrained-layer damping theory that includes only shearing in the damping layer is inadequate for very small or very large values of the shear parameter. Optimal shear-parameter and coverage-length values are determined for a variety of boundary conditions. Results demonstrate the optimal values for the shear parameter and coverage length to obtain maximum damping levels. Plots are derived to determine the optimal coverage length for any shear-parameter value for maximum loss factor.
Original language | English |
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Pages (from-to) | 2998-3011 |
Number of pages | 14 |
Journal | AIAA Journal |
Volume | 46 |
Issue number | 12 |
DOIs | |
State | Published - Dec 2008 |
Externally published | Yes |