Objectives  The coupled double-layer plate structure is common in the hull design, which is of greater importance to investigate its vibration and power flow characteristics.

  Methods  Based on the thin plate theory, the vibration model of finite-size double-layer plate was established by wave method. It was discrete in structure coupling and excitation, and the motion equations of discrete plates were assembled by continuous conditions. The analytical solution of the wave method and the numerical solution of the finite element method was compared to verify the accuracy of the method. Based on this, the influence of the excitation angle and the connector angle and thickness on vibration power flow was analyzed.

  Results  The results show that both the bending vibration power flow and the in-plane vibration power flow increase with the increase of frequency, and the in-plane vibration power flow is much smaller than the bending vibration power flow in the low frequency band, but they approach gradually as the frequency increases; the bending vibration power flow increases with the excitation angle in the whole frequency band, and the in-plane vibration power flow decreases with the excitation angle in the high frequency band; the greater the inclination and thickness of the connector, the lower the vibration power flow of the receiving plate.

  Conclusions  The study in this paper has certain reference value for the design and application of double-layer plate structure.