Visualization of boundary layer separation and passive flow control on airfoils and bodies in wind-tunnel and in-flight experiments
Lukas Popelka1, Jana Kuklova2, David Simurda1, Natalie Souckova1, Milan Matejka1 and Vaclav Uruba1
Institute of Thermomechanics, Academy of Sciences of
the Czech Republic, Dolejskova 5, Prague
8, Czech Republic
firstname.lastname@example.org ; email@example.com ; firstname.lastname@example.org ; Milan.Matejka@fs.cvut.cz ; email@example.com
2 Department of Applied Mathematics, CTU in Prague - Faculty of Transportation Sciences, Konviktska 20, Prague 1, Czech Republic
Published online: 16 April 2012
Infrared camera, Particle Image Velocimetry, smoke-wire, tuft filaments and oil-flow visualization techniques were used for wind-tunnel and in-flight investigation of boundary layer separation, both stall and separation bubbles, related to the low-Reynolds numbers transition mechanism. Airfoils of Wortmann FX66 series and FX66 series wing-fuselage interaction, as well as modern airfoils and their wing-fuselage geometry were subject to study. The presence of previously identified structures in the CFD modelling, such as horse-shoe vortices, was confirmed in the flow.
Wind-tunnels and in-flight measurements on sailplanes were carried out and effect of passive flow control devices - vortex generators - was surveyed; namely counter-rotating vortex generators and Zig-zag type turbulators were applied. Separation suppression and consequent drag coefficient reduction of test aircrafts was reached. PIV investigation was further extended by Time-Resolved techniques.
An important study on structure of the turbulent flow in the lower atmosphere, creating an environment of the soaring flight, was presented.
© Owned by the authors, published by EDP Sciences, 2012