Stochastic reduced-order model for complex beam-like dynamical structures

International audienceThis presentation is devoted to the construction of a stochastic reduced- order model for complex beamlike dynamical structures having a high modal density in the low frequency range. In some cases, in the low-frequency, a dynamical structure can exhibit both the global elastic modes (which characterize this low-frequency range) and numerous local elastic modes. This situation appears for complex heterogeneous structures presenting stiff parts and flexible parts. The presence of these flexible parts induces numerous local reasonance in the low frequency range. Furthermore, in this case, the elastic modes cannot be separated into global elastic modes and local elastic modes. Indeed, due to the coupling between global elastic modes and local elastic modes, the deformation of some global elastic modes have local contributions and the deformation of some local elastic modes have global contributions. Then there are no efficient sorting method which could be used to select the elastic modes as global elastic modes or as local elastic modes