Wake of a Lifting Wing with Cut-In Sinusoidal Trailing Edges

The wake behind a NACA0012 wing at incidence with cut-in sinusoidal trailing edges (TE) is experi- mentally investigated. A wing model with interchangeable trailing edges is used to study their impact on the wake properties. Both vertical and span-wise traverses of hot-wires are done at di erent downstream positions, to obtain the downstream evolution of statistical properties and to perform spectral analysis. Stereoscopic particle image velocimetry is used to study the ow structure in a span-wise/cross-stream plane. Span-wise inhomogeneity of the velocity de cit and of the wake width is observed and explained by the presence of a span-wise/cross-stream ow induced by the cut-in modi cations. Spectral analysis shows a decrease of shedding intensity with shorter TE wavelength, with up to 57% reduction when compared to a straight blunt wing. Blunt sinusoidal TEs exhibit a reduction of span-wise correlation compared to a blunt straight one. A sharp cut-in design is also studied, that exhibits a more broad-band shedding spike at a lower frequency