Conclusion: the presence of downwash over a finite wing reduces the angle of attack that each section effectively sees, and moreover, it creates a component of drag ----the induced drag D And this drag is not produced by viscous friction Explanation of induced drag in physical sense a wing-tip vortices destroy the net pressure balance b the wing-tip vortices contain large amount of translational and rotational energy, and this energy serves no useful purpose. In effect, the extra power should be provided by the engine to overcome the the induced drag
Conclusion: the presence of downwash over a finite wing reduces the angle of attack that each section effectively sees, and moreover, it creates a component of drag ---- the induced drag . And this drag is not produced by viscous friction. Di Explanation of induced drag in physical sense a wing-tip vortices destroy the net pressure balance b the wing-tip vortices contain large amount of translational and rotational energy, and this energy serves no useful purpose. In effect, the extra power should be provided by the engine to overcome the the induced drag
XX Road map and purpose of this chapter XX Support points for our analysis 1. Curved vortex filament 2. Biot-Savart Law 3. Helmholtz's vortex theorems
※ Road map and purpose of this chapter ※ Support points for our analysis 1. Curved vortex filament 2. Biot-Savart Law 3. Helmholtz’s vortex theorems
5.2 The vortex filament. the biot- Savart Law, and helmholtz's theorems ◆ The vortex filament Vortex filament of strength T dv
5.2 The Vortex Filament, The Biot-Savart Law, And Helmholtz’s Theorems The vortex filament
◆Biot- Savart law dlx×r dv 4兀 D Application of Biot-Savart Law 1.To a straight vortex filament of infinite length y=工
Biot-Savart Law 3 4 r dl r dV = Application of Biot-Savart Law 1. To a straight vortex filament of infinite length
2. To a semi-infinite vortex filament 6 r 4Th A
2. To a semi-infinite vortex filament