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In aerodynamics, lift-induced drag, induced drag, vortex drag, or sometimes drag due to lift, is a drag force that occurs whenever a moving object redirects the airflow coming at it. This drag force occurs in airplanes due to wings or a lifting body redirecting air to cause lift and also in cars with airfoil wings that redirect air to cause a downforce. With other parameters remaining the same, induced drag increases as the angle of attack increases.
Source of induced drag:
Lift is produced by the changing direction of the flow around a wing. The change of direction results in a change of velocity (even if there is no speed change, just as seen in uniform circular motion), which is an acceleration. To change the direction of the flow therefore requires that a force be applied to the fluid; lift is simply the reaction force of the fluid acting on the wing.
When producing lift, air below the wing is generally at a higher than atmospheric pressure, while air above the wing is generally at a lower than atmospheric pressure. On a wing of finite span, this pressure difference causes air to flow from the lower surface wing root, around the wingtip, towards the upper surface wing root. This spanwise flow of air combines with chordwise flowing air, causing a change in speed and direction, which twists the airflow and produces vortices along the wing trailing edge. The vortices created are unstable, and they quickly combine to produce wingtip vortices.[2] The resulting vortices change the speed and direction of the airflow behind the trailing edge, deflecting it downwards, and thus inducing downwash behind the wing.
Wingtip vortices also modify the airflow around a wing, compared to a wing of infinite span, reducing the effectiveness of the wing to generate lift, thus requiring a higher angle of attack to compensate, and tilting the total aerodynamic force rearwards. The angular deflection is small and has little effect on the lift. However, there is an increase in the drag equal to the product of the lift force and the angle through which it is deflected. Since the deflection is itself a function of the lift, the additional drag is proportional to the square of the lift.
The total aerodynamic force is usually thought of as two components, lift and drag. By definition, the component of force parallel to the oncoming flow is called drag; and the component perpendicular to the oncoming flow is called lift.At practical angles of attack the lift greatly exceeds the drag. Unlike parasitic drag on an object (which is proportional to the square of the airspeed), for a given lift, induced drag on an airfoil is inversely proportional to the square of the airspeed. In straight and level flight of an aircraft, lift varies only slowly because it is approximately equal to the weight of the aircraft. Consequently in straight and level flight, the induced drag is inversely proportional to the square of the airspeed. At the speed for minimum drag, induced drag is equal to parasitic drag.
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Induced drag in airplane is reduced by?
winglet
How does drag affect a paper airplane?
Drag effects paper airplane just as it affects anything else that moves. It is either parasitic or induced on paper airplanes. Drag may reduce a paper airplanes speed and/or range.
How can you maximize the lift to drag ratio of an aircraft?
Fly the airplane at L/Dmax speed. This is also know as best glide. This speed is found in the POH and represents where induced and parasite drags are at there minimal values for the airplane.
Why is induced drag aslo called lift drag?
Induced drag is the name given to the force of drag 'induced' by the act of increasing lift. Induced drag is directly related to how much lift the wing is producing, and usually angle of attack induced drag is usually caused by flow separations at high angles of attack and wing tip vortices, which is the main form of induced drag. Delta wings have massive induced drag because of their high chord which presents a high frontal area at high angles and leading edge vortices used to produce lift at low speed which generate lots of drag. At high speed and low angle however, the leading edge vortex no longer occurs and the wing has a very low frontal area which decreases the induced drag to almost nothing. Unlike other forms of drag, induced drag actually decreases with higher speed.
What force does an airplane have to overcome in order to stay in flight?
Airplanes have to overcome more than just one force in order to fly. Gravity, of course, is the most obvious one. Drag is another one. The silhouette/cross section/wetted area which the airplane presents to the wind is one obvious form of drag. Then there's induced drag, the friction of the air over the aircraft skin, which increases as the speed of the aircraft increases. There are also incidental sources of turbulence that contribute to induced drag. All of these are overcome with clever design and lots of power.
What is the affect of thrust lift gravity and drag on a plane?
LIFT -- force provided by the wing and in perpendicular direction to the wing. In straight and level flight the lift is exactly equal to the aircraft weight. WEIGHT -- the force pulling vertically down on the airplane due to gravity. In straight and level flight this is equal to the lift. THRUST -- the force that pulls the airplane forward, provided by the propeller or jet engine. If the airplane is flying at a constant speed in level flight, this thrust is exactly equal to the drag. DRAG -- the aerodynamic force on the airplane in the opposite direction of its travel. Drag is due to skin friction, form drag (drag around wheels, struts, etc) and induced drag (produced by the wing as a side effect of lift)
What is the maximum speed an airplane can go?
The maximum speed a airplane can go is a factor of it drag and trust. All planes have a Vne speed witch is the never exceed speed, which is were the amount of drag becomes so great that it will start to damage the aircraft. Many factors have play on this number, such as the camber of the wing, form drag, induced drag, and how strong the frame is. A C-173 Vne is 169, and a SR-22 can go muck 3 or 4. Maximum speed of a airplane is around 1000 km per hour
Basic elements of an airplane flight?
I think you might be referring to the four forces of flight. LIFT -- force provided by the wing and in perpendicular direction to the wing. In straight and level flight the lift is exactly equal to the aircraft weight. WEIGHT -- the force pulling vertically down on the airplane due to gravity. In straight and level flight this is equal to the lift. THRUST -- the force that pulls the airplane forward, provided by the propeller or jet engine. If the airplane is flying at a constant speed in level flight, this thrust is exactly equal to the drag. DRAG -- the aerodynamic force on the airplane in the opposite direction of its travel. Drag is due to skin friction, form drag (drag around wheels, struts, etc) and induced drag (produced by the wing as a side effect of lift)
What is it called when an aircraft is landing and it keeps alike 'floating' above the Runway before touching down?
An airplane begins its "Flare" once it enters "ground effect. Ground effect is what causes the airplane to float because of an increase in lift(what makes an airplane fly). This increase is caused by induced drag, created by the production of lift.
What is zero lift coefficient of drag?
For no lift, The induced drag will be zero. However, there will still be drag due to viscous forces and pressure forces.
How does the drag affect the forward motion of the airplane?
Drag slows the forward movement of aircraft.
What is drag for an airplane?
Drag is a force that acts opposite to the direction of movement of an airplane. Drag is mainly caused by air. The other forces that act on the plane while moving in the air are thrust, lift etc..
