Some experimental flutter results are presented over a Mach number range from about 0.70 to 0.95 for a simple, swept, tapered, flat-plate wing model having a planform representative of subsonic transport airplanes and for the same wing model equipped with two different upper surface winglets. Both winglets had the same planform and area (about 2 percent of the basic-wing area); however, one weighed about 0.3 percent of the basic-wing weight, and the other weighed about 1.8 percent of the wing weight. The addition of the lighter winglet reduced the wing-flutter dynamic pressure by about 3 percent; the heavier winglet reduced the wing-flutter dynamic pressure by about 12 percent. The experimental flutter results are compared at a Mach number of 0.80 with analytical flutter results obtained by using doublet-lattice and lifting-surface (kernel-function) unsteady aerodynamic theories. Mass properties and natural frequencies of three wing models; variables are Mach number, winglet weight/wing weight ratio, wing portion (kg, slugs), modes, basic wing, light winglet, heavy winglet; 5 figures include numeric data.
Preliminary Study of Effects of Winglets on Wing Flutter
1976
25 pages
Report
No indication
English
Preliminary study of effects of winglets on wing flutter
NTRS | 1976
|Preliminary study of effects of winglets on wing flutter
TIBKAT | 1976
|