Flattering of a roof panel

Abstract

It is often observed that a panel on a roof is flattering before it scatters at the critical wind speed when the weight of the panel is balanced to the lift force. The equation of motion for the flattering of the panel is proposed in the paper under an assumption that the lift force is decreased when the panel is away from the roof. According the equation, the flattering is a kind of a free vibration of a system with a mass and a spring which relates with a air layer between the panel and the roof. The frequency of the flattering is not a function of the mass of the panel, but is the function of the flattering displacement and the critical displacement of the lift when the flattering starts.