Towards alleviating vibration response variation based on reduced order modeling and analysis

Periodic structures generally consist of spatially repetitive substructures, which are very common in industrial applications such as turbo-machinery bladed disks. The dynamic responses of these structures are very sensitive to variations in geometry and material properties. Previous studies have shown that, when the substructure-to-substructure coupling is weak, even small variations (referred to as mistuning) among the substructures can cause drastic different in the vibratory response of a periodic structure. The goal of this research is to analyze the variation propagation from substructural properties to the dynamic response of the integral structure, and then inversely identify the design perturbation needed to reduce the response anomaly when such anomaly exceeds the allowable threshold. An order-reduced modeling approach is formulated to facilitate the efficient analysis of vibratory response of the integral structure, and several design perturbations are evaluated in order to reduce the response variations in an example periodic structure.