Generation of Trailing Vortices
When a wing generates aerodynamic lift the air on the top surface has lower pressure relative to the bottom surface. Air flows from below the wing and out around the tip to the top of the wing in a circular fashion. An emergent circulatory flow pattern named vortex is observed, featuring a low-pressure core.
Three-dimensional lift and the occurrence of wingtip vortices can be approached with the concept of horseshoe vortex and described accurately with the Lanchester–Prandtl theory. In this view, the trailing vortex is a continuation of the wing-bound vortex inherent to the lift generation.
If viewed from the tail of the airplane, looking forward in the direction of flight, there is one wingtip vortex trailing from the left-hand wing and circulating clockwise, and another one trailing from the right-hand wing and circulating anti-clockwise. The result is a region of downwash behind the aircraft, between the two vortices.
The two wingtip vortices do not merge because they are circulating in opposite directions. They dissipate slowly and linger in the atmosphere long after the airplane has passed. They are a hazard to other aircraft, known as wake turbulence.
Read more about this topic: Smoke Angel
Famous quotes containing the words generation of, generation and/or trailing:
“Once I prophesied that this generation of Americans had a rendezvous with destiny. That prophecy now comes true. To us much is given; more is expected. This generation will nobly save or mainly lose the last best hope of earth. The way is plain, peaceful, generous just. A way, which if followed, the world will forever applaud, and God must forever bless.”
—Franklin D. Roosevelt (1882–1945)
“Every generation revolts against its fathers and makes friends with its grandfathers.”
—Lewis Mumford (1895–1990)
“As I came home through the woods with my string of fish, trailing my pole, it being now quite dark, I caught a glimpse of a woodchuck stealing across my path, and felt a strange thrill of savage delight, and was strongly tempted to seize and devour him raw; not that I was hungry then, except for that wildness which he represented.”
—Henry David Thoreau (1817–1862)