Vibration analysis of segmented shells coupled with liquid using a mixed Fs-be method

摘要

An analysis is presented for the coupled vibration of segmented shells submerged in or filled with liquid. To improve computing efficiency, the finite strip (FS) technique was used to analyze the segmented shell. As for the liquid area, a special boundary element (BE) was proposed. Compared to the classical boundary element method (BEM), this BE not only guarantees the continuity condition on the liquid-shell interaction plane, but also has fewer unknowns. By using Bemoulli's law and the continuity conditions on the shell-liquid interaction plane, the influence of liquid area was simplified to an added mass matrix; therefore, the shell-liquid system's governing equations, shell's FS equation, and liquid's BE equation are decreased to a group of refined equations that has the same form of FS equation with a modified mass matrix. The method has been applied to a typical segmented shell-liquid system, and the natural frequencies, mode shapes, and response of vibration were calculated numerically. It shows that the method shown here has good efficiency and precision in computing and can analyze the arbitrary rotating shell-liquid system easily.