On the numerical simulations of captive, driven and freely moving cylinder

Abstract

This paper presents the application of turbulence and laminar–turbulent transition models and fluid–structure capabilities to address the flow and response of captive, driven and free moving rigid cylinder for several Reynolds numbers.An investigation on the performance of the turbulence modeling with k–ω SST is presented, verifying the modeling deficiencies for this flow. The Scale Adaptive Simulations (SAS) and the Local Correlation Transition Model (LCTM or γ−Reθ), both combined with the SST, improved the agreement with experimental results for the captive cylinder flow. These studies also involve verification and validation exercises in order to quantify modeling errors of the results herein.In a second step, the use of SST with driven cylinder motions is presented, as well as with the SAS and LCTM. Finally, aiming at free-moving cylinder behavior, this work presents the study of different turbulence modeling practices for the free-moving cylinder in two degrees of freedom (DOF) with low mass ratio.The importance of turbulence effects on the moving cylinder in comparison with the fixed case is investigated. A natural conjecture is that the turbulence modeling strategy is less decisive when the cylinder is moving with driven motion and even less stringent for free motions, as the body response would filter most of the higher order turbulence effects. This issue is investigated as it would allow modeling simplifications in the application of CFD to a range of engineering problems.