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Determination of Structural Damping Using the Impulse Response Function
ISSN: 0148-7191, e-ISSN: 2688-3627
Published May 01, 1991 by SAE International in United States
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This paper shows how the impulse response of each individual resonance in a frequency response function is calculated via a series of weighting functions and then used for damping calculations.
The technique is not new (1)* but previously it has been indicated (2, 3) that when using pseudo-random excitation, T > 2.5τ must be fulfilled in order to make accurate damping measurements, where T is the Fast Fourier Transform record length and τ is the decay constant of the damping.
It is shown that tolerable damping estimates can be made even if the record length T is as small as 0.05τ. This is because the short record length produces an aliasing phenomena on the amplitude of the impulse response function only - not on the slope of the decay.
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CitationGade, S. and Herlufsen, H., "Determination of Structural Damping Using the Impulse Response Function," SAE Technical Paper 911052, 1991, https://doi.org/10.4271/911052.
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