Large Eddy Simulations of flow around a smooth circular cylinder in a uniform current in the subcritical flow regime

Abstract

Three-dimensional flow around a circular cylinder in a steady, uniform current at subcritical Reynolds numbers (Re) is investigated. The flow is simulated using Large Eddy Simulations (LES) with Smagorinsky subgrid scale model. Influences of various numerical parameters are investigated through the statistical values of the drag and the lift coefficients, Strouhal number, pressure distribution and separation angles, as well as through the flow field in the cylinder near wake. The main purpose of the paper is to study the flow around a circular cylinder at Re=13,100, which is chosen due to its applicability to the flow around cylindrical offshore structures in operational conditions, and because it belongs to a not thoroughly studied Re range. However, first the flow around a cylinder in the free stream at Re=3900 is investigated and the results are compared with numerous published results for validation of the chosen LES model. For the higher Re, the results are compared with the published experimental data and the numerical simulations for the similar flow regime. The chosen LES performs well. The results are in reasonably good agreement with previous studies and are discussed through standard hydrodynamic parameters and details of the flow around the cylinder and in the wake.