Author(s)

K.-H. Jeong, G.-M. Lee, T.-W. Kim & J.-I. Kim

Abstract

A theoretical study on the natural frequencies and the mode shapes of a perforated plate in contact with an ideal liquid is presented. In the theory, it is assumed that the plate is simply supported along the edges and the liquid is in contact with the lower surface of the plate. The identical square holes in the plate with a square array are considered. A compatibility requirement on the contact surface between the plate and the liquid is applied for the liquid–structure interaction and the Rayleigh–Ritz method is used to calculate the eigenvalues of the system. The proposed theoretical method for the plate coupled with the liquid is verified by observing a good agreement with the three-dimensional finite element analysis result. Keywords: hydroelastic vibration, perforated plate, liquid–contacting, Rayleigh– Ritz method, fluid-structure interaction, natural frequency, rectangular holes. 1 Introduction The perforated plates with a number of holes are used in the commercial nuclear power plants. However, it is very difficult to estimate dynamic characteristics of such a perforated plate. Moreover, the dynamic behavior of the plates in contact with a fluid is very complicated due to the fluid–structure interaction. The powerful numerical tools such as FEM (finite element method) or BEM (boundary element method) make approximate solutions to a simple fluid– structure interaction problem possible. However the use of these methods in the perforated structures requires enormous amounts of time for modeling and computation. The previous study [1] on the perforated plates focused on the

Keywords

hydroelastic vibration, perforated plate, liquid–contacting, Rayleigh– Ritz method, fluid-structure interaction, natural frequency, rectangular holes.