Flow-induced oscillations of circular cylinder in a narrow channel

Abstract

The problem of transverse auto-oscillations of a cylinder in a flow of a viscous incompressible fluid in a plane channel is considered. The fluid-structure interaction problem is solved in a complete conjugate formulation, in which a continuous medium and a moving rigid body are described as a general dynamical system without splitting into dynamic and hydrodynamic components. The mesh-free method is the most suitable for solving this problem, since the flow region changes not only the form but also the connectivity at the time when the body touches the wall. Another difficulty is connected with the need to construct an adequate model of elastic collisions of bodies in a liquid. Calculations are performed using the fully Lagrangian method of viscous vortex domains (VVD). A model has been developed for the elastic collision of a body with a fixed wall taking into account the influence of a liquid. The mechanism of self-oscillations is revealed. It is shown that the restitution coefficient characterizing the elastic interaction of colliding bodies is an important parameter of the problem under consideration.