A remark about the decoupling approximation of damped linear systems. (English) Zbl 1258.70034
Summary: A common approximation in the analysis of non-classically damped systems is to ignore the off-diagonal elements of the modal damping matrix. This procedure is termed the decoupling approximation. Contrary to widely accepted beliefs, it is shown numerically that over a finite range, errors due to the decoupling approximation can continuously increase at any specified rate while the modal damping matrix becomes more and more diagonal.
MSC:
| 70J35 | Forced motions in linear vibration theory |
References:
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