On two-dimensional predictions of turbulent cross-flow induced vibration: Forces on a cylinder and wake interaction

摘要

In this paper a typical fluid-structure interaction scenario is investigated for a turbulent flow past a circular cylinder at a relatively low subcritical Reynolds number. Numerous experimental and numerical studies have been undertaken for a baseline Reynolds number of 4,000 involving a stationary cylinder to study in detail the near wake mean flow and turbulence characteristics. These studies conclusively show that the turbulent wake displays significant coherent periodic structures of large eddies that could be adequately and profitably resolved by "low order modelling" of turbulence. In this study, an unsteady numerical framework is employed for the simulations, incorporating an Arbitrary Lagrangian-Eulerian (ALE) method for the associated grid deformation to simulate the coupled motion of the circular cylinder with a single degree of freedom in the initial zone in a typical cylinder-flow response map or what is called "initial regime". Particular attention is paid towards resolving the large scales of the fluid motion and the inherent coupling of the cylinder's motion towards the associated evolution of the time averaged flow field. The flow-induced vibration effects regarding the kinetic energy exchange between the mean flow and the coherent periodic scales are investigated further. The predictions discussed and analyzed in detail in the paper display reasonable agreement with the chosen benchmark tests of the stationary cylinder and suggest that the conclusions outlined regarding the coupled flow-cylinder system potentially provides a valuable contribution to the state of the art.