すきまを考慮した3次元片持ち柔軟平板のフラッタ解析

抄録

When machines and structures exist in a fluid, they are affected by fluid. Therefore, the unstable vibration such as flutter may occur and induce an accident problem. So, it is important to predict the vibration caused by the influence of fluid. Here, a flutter of flexible plate is investigated. As examples of flutter of flexible plate, countermeasures against flutter in power generation turbines and nuclear power fields, vibration of vocal cords, the oscillating doom roof, a high-speed printing machine are enumerated. In this analytical method, dynamic stability of rectangular flexible plate is considered in three-dimensional channel. Channel wall is considered rigid and established only thickness direction of the flat board. So, it is possible to investigate effect of channel wall. The fluid assumed as an ideal flow in a subsonic domain, and the fluid pressure is calculated using the velocity potential theory. The unsteady fluid pressure is determined by using the integral equations for the pressure along the span and the pressure along the chord under the boundary conditions in the Fourier space. Applying the Galerkin method to the equation of motion of an elastic plate, the three-dimensional coupled equation of motion of a flexible cantilevered plate is derived. Changing the mass ratio, aspect ratio and gap ratio, the critical flow velocity and vibration made of the plate are investigated. And, the relationship among mass ratio, aspect ratio and gap ratio are investigated.