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Unconstrained layer damping involves gluing proprietary high damping material to thin metal panels. As the panel vibrates, it bends, stretching the damping material and some vibration energy is dissipated as heat.
Constrained-layer damping is a mechanical engineering technique for suppression of vibration. Typically a viscoelastic or other damping material, is sandwiched between two sheets of stiff materials that lack sufficient damping by themselves. The ending result is, any vibration made on either side of the constraining materials (the two stiffer materials on the sides) are trapped and evidently dissipated in the viscoelastic or middle layer.
Hand calculations for calculating the overall loss factor of FLD:
Hand calculations for calculating the overall loss factor of CLD:
