LAUSR

Flow control devices are one of the most commonly studied fields of aerodynamic research in the world. This is because improvements in the aerodynamic performance of any vehicle lead directly to save fuel and money and reduce operational costs of them. Another reason is that flow control can reduce the risk of aerial vehicles operating near complex structures which can generate high turbulence intensity levels, supposing a risk for its maneuvers. A passive flow control device used for improving the flow on the ramp of an aircraft carrier is the Columnar Vortex Generator (CVG). Using this device, encouraging results to improve the flow for aerial vehicles which operate on those ships, have been obtained. However, CVG detailed working and vortex generation is not fully known. For that reason, the aim of this paper is to present the results obtained in wind tunnel tests of this passive flow control device called Columnar Vortex Generator (CVG). The flow behavior at the front, rear and especially inside it was analysed. A smoke visualization has been made to the CVG model as a first approach to the flow structure surround and inside the CVG. Flow inside the CVG and specifically its vortex generated has been also analysed using velocity maps obtained by Particle Image Velocimetry (PIV). Tangential and axial PIV planes have been obtained to characterise the vortex and its movement inside the device. These resultant velocity maps have been used to compare the vortex with theoretical models (Rankine and Oseen-Lamb vortex) and establish a new model that predicts the velocity profiles of the vortex generated inside the CVG. Finally, new possible applications using the CVG to improve the flow over a building roof and over the flight deck of a frigate under stern wind is tested by means of PIV in the wind-tunnel.