Wing Twist

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  Wing twist is of two types named as geometric twist and aerodynamic twist:- Geometric Twist Different angles of attack at wing root and tip. Wash in Tip chord has a higher angle of attack than that of root chord. Wash out Angle of attack at tip is lower than that at wing root. It is useful in reducing tip vortices. Aerodynamic Twist Difference between zero-lift lines of airfoils at wing root and near the tip. Airfoils at root and near the tip have different zero lift angles of attack.
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Centre of Pressure

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When an Object moves through fluid, velocity varies on the surface of the object which creates a pressure difference around the object which is greatest near the leading edge. All the distributed forces due to pressure were replaced by a single resultant force, this single force would act less than halfway back along the chord. The position on the chord at which this resultant force acts is called the Centre of Pressure. The idea of center of pressure as average location of pressure variation is very similar to the center of gravity as the average location of weight.


The center of pressure moves along the chord line when angle of attack is altered. At normal cruising speeds, the center of pressure is positioned on the chord line near the center of the airfoil. When angle of attack increases center of pressure shifts towards the leading edge and the magnitude of total resultant force increases.







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