Wingtip vortices: Difference between revisions

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Wingtip vortices are vortices that develop at the edge of a wing as it flies through the air (or potentially another fluid). Wingtip vortices dramatically reduce the lift generated by the wing, and are therefore critically important in aerospace engineering.

As a wing flies through the air, it generates a low pressure zone on top of the wing through the Bernoulli effect. Fluids naturally flow from high to low pressure and the relatively high pressure air below the wing has a natural tendancy to flow to the top of the wing. The air naturally cannot flow around the leading or trailing edge of the wing due to airspeed, but it can flow around the end. Thus air flows from below the wing, out around the edge to the top of the wing in a circular fashion. This raises the pressure on top of the wing and lowers the overall lift that the wing can produce.

Luckily, wingtip vortices really only affect the portion of the wing closest to the end. Thus the longer a wing is, the smaller the affected fraction of it will be. As well, the shorter the chord of the wing, the less opportunity air will have to form vortices. Thus, for an airplane to be most efficient, it should have a very wide high aspect ratio. This is evident in the design of long-range airliners and gliders, where efficiency is of critical importance. However, increasing the wingspan reduces the manoueverability of the aircraft, which is why combat and aerobatic planes usually feature short, stubby wings despite the efficiency losses.

Another method of reducing wingtip vortices is winglets, as seen on a number of modern airliners such as the Airbus A340. Winglets work by interfering with the formation of the vortex, thereby effectively increasing the aspect ratio of the wing. Winglets can yield very worthwhile economy improvements on long distance flights.

Since vortices cause a low-pressure area at their centre, sometimes water precipitates out to form clouds in the vortices allowing wintip votices to be seen. The is most common on fighter aircraft when they are pulling high G manouevres

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 As a wing flies through the air, it generates a low pressure zone on top of the wing through the [[Bernoulli effect]]. Fluids naturally flow from high to low pressure and the relatively high pressure air below the wing has a natural tendancy to flow to the top of the wing. The air naturally cannot flow around the leading or trailing edge of the wing due to airspeed, but it can flow around the end. Thus air flows from below the wing, out around the edge to the top of the wing in a circular fashion. This raises the pressure on top of the wing and lowers the overall lift that the wing can produce.
-Luckily, wingtip vortices really only affect the portion of the wing closest to the end. Thus the longer a wing is, the smaller the affected fraction of it will be. As well, the shorter the [[Chord (aircraft)|chord]] of the wing, the less opportunity air will have to form vortices. Thus, for an airplane to be most efficient, it should have a very wide high [[aspect ratio]]. This is evident the design of long-range [[airliner]]s and gliders, where efficiency is of critical importance. However, increasing the wingspan reduces the manoueverability of the aircraft, which is why combat and aerobatic planes usually feature short, stubby wings despite the efficiency losses.
+Luckily, wingtip vortices really only affect the portion of the wing closest to the end. Thus the longer a wing is, the smaller the affected fraction of it will be. As well, the shorter the [[Chord (aircraft)|chord]] of the wing, the less opportunity air will have to form vortices. Thus, for an airplane to be most efficient, it should have a very wide high [[aspect ratio]]. This is evident in the design of long-range [[airliner]]s and gliders, where efficiency is of critical importance. However, increasing the wingspan reduces the manoueverability of the aircraft, which is why combat and aerobatic planes usually feature short, stubby wings despite the efficiency losses.
 Another method of reducing wingtip vortices is [[winglet]]s, as seen on a number of modern airliners such as the [[Airbus A340]]. Winglets work by interfering with the formation of the vortex, thereby effectively increasing the aspect ratio of the wing. Winglets can yield very worthwhile economy improvements on long distance flights.