Semi-analytical modeling and dynamic characteristic analysis of rotational drum-blade-disk system

The coupled drum-blade-disk system (DBDS) is a representative structural component in aero-engines. The system can be characterized by complicated dynamic behavior due to interactions among flexible components. This study proposes a novel semi-analytical model that simultaneously considers the flexibility of the drum, disk, and blades, as well as key rotational effects including centrifugal stiffening, spin softening, and Coriolis forces. Unlike existing models that rely heavily on finite element analysis or simplify component interactions, the proposed model provides a compact yet accurate formulation by combining Hamilton’s principle with the Galerkin method. The proposed model is validated through comparison with results of the natural frequencies and mode shapes from the literature, modal test experiments, and ANSYS simulations. The results indicate that the proposed semi-analytical model of DBDS has high numerical calculation accuracy on natural characteristics and dynamic responses. Numerical analyses further reveal the influence of drum length and radius on the natural frequencies of the system. This work offers an efficient and physically insightful tool for vibration prediction and parameter design in complex rotating structures, with potential benefits for improving aero-engine reliability and design optimization.