Vortex Induced Vibrations

A. Leonard Theodore von Kármán Professor of Aeronautics,
EmeritusGraduate Aeronautical LaboratoriesCalifornia Institute of TechnologyPasadena, CA Vortex shedding from a bluff body can impose significant, time-dependent forces on the body. If the body is freely oscillating, the amplitude of the resulting vibration can lead to disastrous consequences in some instances or, on the plus side, can be the essence of a proposed power generation scheme. The amplitude and frequency of the motion depends on the shape of the body and on four parameters: nondimensional mass, damping coefficient, spring constant or stiffness, and Reynolds number. In some cases, the expected resonant behavior occurs when the vortex shedding frequency is close to the natural vibration frequency of the mechanical system and the damping is low. But there are important ranges of these parameters that yield contrary results. Laboratory and computational experiments of flow past a freely oscillating circular cylinder will be discussed along with a new theoretical approach that requires only three parameters: effective stiffness, damping, and Reynolds number, and takes the mystery out of some of the mysterious results reported in the literature.

Location: Ronald Tutor Hall of Engineering (RTH) - 526

Audiences: Everyone Is Invited

Contact: April Mundy