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Magnus effect

Magnus Effect

 

 Magnus effect – The Magnus Effect is the lifting force produced when a rotating cylinder produces a pressure differential. This is the same effect that makes a baseball curve or a golf ball slice.     

When a rotating cylinder or ball is spinning in a fluid, it creates a boundary layer around itself, and the boundary layer induces a more widespread circular motion of the fluid.   

If the body is moving through the fluid with a velocity V, the velocity of the fluid close to the body is a little greater than V on one side and a little less than V on the other. This is because the induced velocity due to the boundary layer surrounding the spinning body is added to V on one side, and subtracted from V on the other.   

In accordance with Bernoulli’s principle, where the velocity is greater the fluid pressure is less; and where the velocity is less, the fluid pressure is greater. This pressure gradient results in a net force on the body, and subsequent motion in a direction perpendicular to the relative velocity vector (i.e. the velocity of the body relative to the fluid flow).   

The Magnus effect is currently used to create lift with a rotating cylinder at the front of a wing that allows flight at lower horizontal speeds.  Magenn Power Inc has created a lighter-than-air high altitude wind turbine called MARS that uses the Magnus effect to keep a stable and controlled position in air. According to Magenn Power’s website the   

Magenn Power Air Rotor

Magenn Power Air Rotor

 

  

 

  

 

  

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