The wavy leading edge performance for a very thick airfoil

Resumo

© 2017 by the American Institute of Aeronautics and Astronautics, Inc. All rights reserved.The aim of this work is to investigate the wavy leading edge phenomena for the very thick airfoil NACA 0030 by experimental investigation correlating force measurements with mini-tuft and oil flow visualization data at low Reynolds number regime. Experimental tests were carried out at subsonic blower-type wind tunnel of open loop with closed section at ITA (Technological Institute of Aeronautics). A set of four very thick airfoils were tested composed by one smooth configuration and three wavy leading-edge configurations (A= 0.03c, λ = 0.40c; A= 0.03c, λ = 0.11c; A= 0.11c, λ = 0.40c). The wavy leading edge geometry variation and Reynolds number effects were evaluated at range of Reynolds number between 50,000 and 290,000. For the highest Reynolds number condition, the results show worse aerodynamic performance for wavy leading edge when compared to previous studies of thinner airfoils. However, at Reynolds number 120.000, the configuration with A= 0.03c and λ = 0.11c presents a unprecedented result on literature overcoming the baseline maximum lift coefficient in 19,4% and the stall angle in 44%. In addition, the flow visualization results indicate that the leading edge stall characteristics at airfoils lead the tubercle configurations for better aerodynamic performance.