Free vibration behaviors and vibration correlation technique of hierarchical Isogrid stiffened composite cylinders

The objective of this paper is to investigate the free vibration behaviors of novel hierarchical Isogrid stiffened cylinders (HISCs) by free vibration experiments and numerical simulations. A nondestructive vibration correlation technique (VCT), incorporating with material properties of unidirectional laminate, rule of mixtures, finite element modeling (FEM) and free vibration experimental results, was proposed to evaluate the composite properties of HISC which were greatly affected by the manufacturing process. The fiber volume fraction was selected as a critical factor in the analysis and redefined by the VCT to newly define the composite properties of HISC. The effect of hierarchical structure on the fundamental frequency was investigated based on newly determined material properties. Meanwhile, the advantages of the HISC over the Isogrid stiffened cylinder (ISC) were discussed and the current structure can work as a reference for the optimal design of ultra-light and stiff HISC.

Automated summary

The paper investigates the free vibration behaviors of novel hierarchical Isogrid stiffened cylinders (HISCs) through experiments and simulations. A nondestructive vibration correlation technique (VCT) is proposed to evaluate composite properties of HISC affected by manufacturing process, redefining fiber volume fraction. The hierarchical structure's effect on fundamental frequency is studied, along with advantages over Isogrid stiffened cylinder (ISC) for optimal design reference.