Additive ABH for vibration attenuation of rotating disk-shell coupled structures

To address the weak strength and stiffness of acoustic black holes (ABHs) in vibration reduction applications of rotor system, this paper proposes a disk-shell coupled structure with an additive ABH, combined with a damping layer to achieve vibration attenuation under rotating conditions. Taking the rotational effect into account, the Rayleigh-Ritz method is used to establish the equations of motion, combining Sanders shell theory and Mindlin plate theory. Different artificial spring groups are used to simulate the coupling and boundary conditions. The total energy of the system is substituted into the Lagrange equations, which are then transformed into a system of first-order ordinary differential equations using state-space representation method for solution. The correctness of the proposed method is verified by comparing numerical results with simulation analysis and experimental results. Numerical analysis demonstrates the vibration reduction effect of the ABH on the rotating disk-shell coupling structure, and the influences of ABH dimensions on the vibration reduction effect are investigated using the modal loss factor as an evaluation metric. The results show that the ABH effectively reduces vibration in the high-frequency region of the rotating disk-shell structure, but its ultimate vibration reduction performance decreases with increasing rotational speed. At low speeds, a larger ABH length and smaller uniform thickness are more conducive to vibration reduction, whereas at high speeds, a smaller ABH length combined with a smaller uniform thickness yields better performance.