EFFECTS OF LEADING-EDGE RADIUS AND MAXIMUM THICKNESS-CHORD RATIO ON THE VARIATION WITH MACH NUMBER OF THE AERODYNAMIC CHARACTERISTICS OF SEVERAL THIN NACA AIRFOIL SECTIONS

摘要

A wind—tunnel investigation has been made to determine the effects of leading-edge radius and maximum thickness-chord ratio on the variation with Mach number of the aerodynamic characteristics of several thin symmetrical NACA 4-digit-series airfoil sections. The Mach number range of the investigation, was from 0.3 to approximately 0.9 and the corresponding Reynolds number range from approximately 1 X 106 to 2 x 106.nThe variations with Mach number of the lift, drag, and pitching moment for a 4-percent-chord-thick airfoil section are not significantly affected by a change of leading-edge radius from 0.18 to 0.53 percent of the chord. A similar conclusion can he drawn for a leading-edge—radius variation from 0.10- to 0.40-percent chord on a 6-percent-chord-thick section.