Modeling and vibration analysis of rotating cylindrical–cylindrical shells with multi-ring hard-coating damping under arbitrary boundary conditions

The work focuses on analyzing the traveling wave vibration characteristics of high-speed rotating multi-ring hard-coating damping cylindrical–cylindrical shells with discontinuous connections under arbitrary boundary conditions. Considering the single shell is frequently bolted to other shell structures, with the junction only made within the bolt action area. By improving the distribution of a conventional entire circumference continuous artificial spring, a discontinuous arc connection is established to simulate a bolted junction condition. Simultaneously, the arbitrary boundary conditions are established by employing the artificial spring technique. Given the existence of appendages along with the lightweight requirement, a multi-ring hard-coating application strategy on the shells is better suited for actual projects. Therefore, based on the parametric multi-partitioning method, the multi-ring application strategy model is constructed for effective suppression of harmful vibration. The Sanders’ shell theory and the Rayleigh–Ritz method are combined to derive dynamic equations, while the matrix eigenvalues are calculated by utilizing the state space method. Further, the influences on parameters like connection stiffness, hard-coating ratio, length ratio, etc. upon the traveling wave frequencies and modal loss factor of the shell structure are discussed in detail.