Investigation of vortex-generators within a turbulent boundary layer flow using time-resolved tomographic PIV

The present paper describes the application of time-resolved tomographic PIV [1, 2] to a turbulent boundary layer flow influenced by vortex generators. Flow control is a promising means to increase the performance of aerodynamic systems. Both active (e.g. suction) and passive (e.g. vortex generator vanes) devices have successfully been used in aerodynamic research as well as commercial application. One big area of application is the suppression or at least delay of separation of the flow around airfoils at high angles of attack. As a general rule passive devices have the advantage of being cost-effective and simple to setup; Successful examples to this are vortex generator vanes [3]. The principle of operation is based on the increase of momentum exchange from the free flow into the boundary layer. For a deeper understanding and the optimization of these mechanisms, three-dimensional measurements of the flow can provide valuable information. Instantaneous recordings of the complete volume can serve as a data basis for numerical simulations, especially if the data is also time-resolved.