Fluid structure interaction of flow induced vibration. A study of laminar and turbulent flow fields

The flow around a circular cylinder is a traditional problem of fluid dynamics, knowledge of which is essential for basic understanding as well as for technical applications, such as large buildings, bridges, standpipes, heat exchanger tubes, rods, transport pipelines, poles and cables, all of which attracted widespread attention. A circular cylinder usually experiences boundary layer separation. In certain Reynolds number range, a periodic flow motion develops in the wake as a result of boundary layer vortices being shed alternatively from either side of the cylinder leading to unwanted structural vibrations. In order to calculate the cylinder response to the flow, a computational method to solve the flow around the body and its resultant vibration using Fluent is previously developed and validated. The present study details the extension and verification using the same method by incorporating flow turbulence through its modeling. The incoming free stream flow is uniform with Reynolds number based on diameter of 3.8 and 12.7mm. Results for the unsteady shedding flow behind a circular cylinder and its vibration are presented with experimental comparisons, along with a comparison of two-dimensional laminar as well as turbulent models of the flow for fully coupled interaction. The Strouhal number and structural displacements are in good comparison with the experimental data of showing the capability of FSI method using Fluent to tackle laminar as well as turbulent flows. (author)