LIFT AND PITCHING MOMENT AT LOW SPEEDS OF THE NACA 64A010 AIRFOIL SECTION EQUIPPED WITH VARIOUS COMBINATIONS OF A LEADING-EDGE SLAT, LEADING-EDGE FLAP, SPLIT FLAP, AND DOUBLE-SLOTTED FLAP

摘要

A two-dimensional wind-tunnel investigation at low speeds was made of the NACA 64A010 airfoil equipped with various combinations of a leading-edge slat, leading-edge flap, split flap, and double-slotted flap. Optimum slat positions were determined for a Reynolds number of 6 million for the model with no trailing-edge flap and with the two trailing-edge flaps deflected. Section lift and pitching-moment characteristics of the various model arrangements were ascertained for Reynolds numbers of 2, 4, 6, and 7 million.nThe increases in the maximum section lift coefficient produced by the leading-edge flap or by the leading-edge slat in combination with either of the trailing-edge flaps were approximately equal to the sum of the increments produced by each of the high-lift devices deflected individually. Extension of the leading-edge slat and deflection of the leading-edge flap produced increments in climax of about 0.83 and 0.66, respectively. Deflection of either leading-edge high-lift device caused the aerodynamic center to move forward. In the case of the leading-edge slat, the aerodynamic center moved forward to approximately the quarter point of the extended chord.nAn empirical method is presented for determining, to a first approxi¬mation, the slat position which produces the highest maximum section lift coefficient for a given slat deflection angle.