NACA-TN-2502

Abstract

Force, moment, pressure-distribution, and boundary-layer measurements are presented for a series of five airfoil sections. The stalling characteristics of these airfoil sections at low speeds are of three types: <br>1. Trailing-edge stall (preceded by movement of the turbulent separation point forward from the trailing edge with increasing angle of attack) <br>2. Leading-edge stall (abrupt flow separation near the leading edge generally without subsequent reattachment) <br>3. Thin-airfoil stall (preceded by flow separation at the leading edge with reattachment at a point which moves progressively rearward with increasing angle of attack) <br>The role of the boundary-layer flow and separation processes in relation to stalling as well as the sensitivity of the stall to factors which influence boundary-layer growth, such as Reynolds number, is discussed.