Influence of differnet measurement settings and methods on obtained damping values

Due to the desire for shorter development periods and higher cost efficiency, the demand for improved simulations of structural dynamical behaviour is increasing. One requirement for a reliable numerical model is sufficiently accurate geometrical and material parameters. Whereas the effort to obtain precise values for density and stiffness is, at least for monolithic metals, relatively low, it can still be difficult to obtain reliable damping values. These uncertainties can result in a deviation between simulation and experiment. Reasons for this deviation can be quite often located in the numeric as well as in the experimental setup. This study concentrates on the influence of settings and parameters, such as sampling frequency, block length or windowing used during the experiment. Since the influence of a single parameter on the determined damping value is hard to investigate with real structures, virtual modelling is used in order to generate the dynamical behaviour of a structure in the time domain. For further investigation, an FFT and a modal analysis will be performed on those data. Through this procedure, different sources of error can be identified and quantified.