Images from CAMRAD II Calculations

The images presented below are taken from calculations performed using CAMRAD II.

hovering rotor; tip vortices are green and blue, lift is red, downwash is magenta

movie file (1.07 Mb)

note the contraction of the wake and the influence of the tip vortex from the preceding blade on the loading

rotor in forward flight (advance ratio 0.15); tip vortices are greens, bound circulation is purple, lift is violetred, downwash is deeppink; red arrows are flap bending moments and net rotor force

movie file (1.35 Mb)

note the position of the tip vortices above the blades on the sides of the disk, the rollup of the wake into two super vortices, and the variation of the bending loads with azimuth

helicopter in low speed forward flight (60 knots); tip vortices are greens, blade normal force and inplane force are violetred and purple (not to same scale)

movie file (1.22 Mb); bvi movie file (1.07 Mb)

note the blade-vortex interaction on the advancing and retreating sides

helicopter in high speed forward flight (160 knots); tip vortices are greens, blade normal force and inplane force are violetred and purple (not to same scale)

movie file (0.71 Mb)

note the negative loading on the tip of the advancing blade

rotor at high thrust (advance ratio 0.23, thrust coefficient divided by solidity 0.13); blade normal force is red and inplane force is purple; rotating frame perspective, loads shown on blade at azimuth angle 0 to 360 deg (0 azimuth downstream)

movie file (0.21 Mb)

tandem helicopter in forward flight (100 knots), with slung load; front rotor tip vortices are greens, rear rotor tip vortices are purples, downwash from rotor's own wake is midnightblue, downwash from other rotor's wake is darkgreen; red cables are to top of slung load; fixed frame perspective

movie file (0.50 Mb)

note that the wake vorticity is deposited in the air as the helicopter flies by

highly swept rotor at low speed (advance ratio 0.10); tip vortices are greens, bound circulation is darkgreen, downwash is lightgreen; blade flap bending loads are red, blade lag bending loads are orange; rotating frame perspective

movie file (0.77 Mb)

rotor with trailing-edge flap (advance ratio 0.30); tip vortices are greens, bound circulation is purple, downwash is red

movie file (1.16 Mb); closeup movie file (1.15 Mb)

note the trailed vorticity from the flap edges, and the bending of blade

hovering helicopter encountering a large amplitude gust (transient duration 1.5 sec, step gust starts at 0.1 sec); blade normal force is green, red arrow is net rotor force; fixed frame perspective

movie file (1.86 Mb)

helicopter encountering a large amplitude gust in forward flight (100 knots, transient duration 1.5 sec, step gust starts at 0.1 sec); blade normal force is green, red arrow is net rotor force; fixed frame perspective

movie file (0.99 Mb)

helicopter in forward flight (60 knots); main rotor tip vortices are greens, tail rotor tip vortices are darkgreen, tail rotor blade lift is red

movie file (1.82 Mb)

note the influence of the main rotor wake on the tail rotor

airplane with large propeller (ratio flight speed to tip speed 0.95); vortices from propeller tip and root and from wing tips are greens, wing and blade loading are red

movie file (1.36 Mb)

note the influence of the propeller wake on the wing loading