Correction of Analytical Models for Damped Linear Systems Using Experimentally Obtained Forced Vibration Responses
The dynamic behaviour of mechanical systems can usually be described by discrete analytical models which are obtained through an analytical systems analysis. Errors are mainly caused by the simplifications which are necessary in order to create a physical model of the continuum. They can possibly result from discretization as well as from deviations of the system parameter values. Discretization errors, which will not be regarded here, influence primarily the order of the model given be the number of degrees of freedom as well as by the number of modes. The deviations of the mass-, stiffness- and damping parameters are due to insufficient knowledge of the behaviour of the structure, the boundary and the connection elements. In general there is no difficulty in evaluating the inertia properties to a sufficient degree of accuracy. The evaluation of stiffness parameters is more difficult, and the evaluation of the damping parameters by means of an analytical systems analysis only is in general not possible. Thus in the derivation of damping matrices — which will be discussed later — use should be made of experimental data. Due to the above — mentioned error possibilities, a verification of the analytical model may be necessary, and if certain analysis — test correlation requirements are exceeded the model has to be adjusted.
KeywordsStiffness Matrix Correction Coefficient Correction Strategy Measured Frequency Response Present Correction
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