WER 27: Effects of spoiler hingeline location on the NACA 23024 airfoil

Abstract

Two-dimensional wind tunnel tests were conducted to determine the aerodynamic effects of spoiler hingeline location on the NACA 23024 airfoil . The particular motivation for these studies is potential application of spoilers for overspeed control of wind turbines . For the tests, 10% chord spoiler at 90 degrees angle of deflection and 20% chord spoiler at 60 , 90, and 120 degrees angles of deflection were used. The locations of attachment for these spoilers were at 10, 20, 30 , 40, 60 and 80 percent along the wing chord. The wind tunnel tests were conducted at Reynolds numbers of 0.6xlo 6 and of 1.0x10 6 , which correspond to Mach numbers of 0.1 and 0 . 2, respectively . Results of the study show that when the spoiler hingeline is relocated toward the leading edge of the airfoil, the spoiler effectiveness in producing reduced lift and added drag is increased , especially at high angles of attack below the stall . The leading edge suction force is decreased as the spoiler hingeline is relocated toward the leading edge of the airfoil. The trend of the results agrees with theoretical predictions. It is recommended that tests of spoilers be conducted on a rotating blade.