STEADY BLOWING / SUCTION INTO TURBULENT BOUNDARY LAYER OF A SYMMETRICAL AEROFOIL SECTION

The efficiency of steady air blowing / suction into the turbulent boundary layer of the NACA 0012 aerofoil section in an incompressible flow was studied experimentally. The blowing / suction was carried out through finely perforated sections located on the adjacent sides of the wing and being parts of its streamlined surface. The studies were performed at the Reynolds number Re_c = 0,7*10⁶ in the range of angles of attack α = –6 ÷6°. The obtained results clearly indicate the ambiguous nature of the combined control action in the form of blowing / suction on the aerofoil aerodynamic characteristics. The maximum gain in lift-to-drag ratio of about 1.8 units is achieved at zero angle of attack α. An increase in α leads to a decrease in the effectiveness of this method of action on the boundary layer.

Keywords:
aerofoil, boundary layer, finely perforated section, blowing / suction, lift-to-drag ratio, lifting force, drag. 
УДК 532.526.4 + 532.546.6 + 533.69.048

STEADY BLOWING / SUCTION INTO TURBULENT BOUNDARY LAYER OF A SYMMETRICAL AEROFOIL SECTION