RT journal article
T1 Experimental observations of the effects of spanwise blowing on the wingtip vortex evolution at low Reynolds numbers
A1 García Ortiz, José Hermenegildo
A1 Blanco Rodriguez, Francisco J.
A1 Parras Anguita, Luis
A1 del Pino Peñas, Carlos
A2 Ingeniería Mecánica y Diseño Industrial
AB We experimentally investigate the effect of a spanwise continuous jet on the trailing vortex behind awing model NACA0012 airfoil (AR = 2) using a local injection at a fixed angle of attack, α = 9◦ . Threedifferent chord-based Reynolds numbers, Re, and different blowing continuous jets characterized bythe momentum coefficient, Cμ , have been analyzed by means of 2D-PIV measurements. We showhow these jets are good candidates to reduce the strength of the wingtip vortices at the lowestReynolds number considered, e.g., Re = 7 × 103. Conversely, the blowing has a weak influence onthe vortex strength at Re = 15 × 103 and 20 × 103. Making use of classical vortex models weprovide a set of theoretical parameters which offer a general, and quantitative characterization ofthe effect of continuous blowing jets on the wingtip vortex as we vary the Reynolds number. Besides,the mode decomposition analysis from 2D velocity fields concludes that the perturbed flow structurehas a predominant axisymmetric mode at Re = 7 × 103. However, the predominant mode is notonly m = 0, but also |m|=1 for greater Reynolds numbers. Two different perspectives are discussedto support the mixing process between the spanwise blowing and the wake behind the wing model.Firstly, the theoretical parameter that corresponds to the exponent of the vortex decay in Moore &Saffman model is n = 1, so the vortex formed downstream is inviscid, and consequently, the turbulentdiffusion is acting rapidly at Re = 7 × 103 . Secondly, we pay our attention to the location of theinjection relative to the streamwise vorticity formed downstream. We observe that the lower thevorticity level downstream the injection area, the higher the influence to break the wingtip vortex.
PB Elsevier
SN 0997-7546
YR 2020
FD 2020-04
LK http://hdl.handle.net/10498/34931
UL http://hdl.handle.net/10498/34931
LA eng
DS Repositorio Institucional de la Universidad de Cádiz
RD 08-nov-2026