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Centre of pressure

  1. Jul 23, 2012 #1
    Is centre of pressure the same way they represent curl in mathematics ? i.e representation of pressure condensed to a single point?

    Also,on a tv show,the presenter said this about the air-brakes on a P-28 fighter,"The air-brakes change the centre of pressure thereby allowing the wind-flow to stick at high speeds".What does he mean by this?
    ASIDE:Since I guess the representation of centre of pressure is pretty similar to curl,could someone please tell me why mathematicians use the gradient to represent curl?

    As a engineer,I'm more used to seeing exercises where curl is calculated using the position vector 'dr' and then taking the line integrals.How can I prove that the gradient x field=line integral stuff ???
    Last edited: Jul 23, 2012
  2. jcsd
  3. Jul 23, 2012 #2

    Simon Bridge

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    Center of pressure is like a center of mass. In aircraft it is kinda where the wing's lift appears to be acting.

    The description in the documentary sounds like garbled rubbish to me. Clearly the air-brake changes the pressure distribution dramatically giving you a lot of drag which could be described as making the air stick ...

    AFAIK. mathematicians represent curl as, well, curl. You mean [itex]\text{curl}(\vec{V}) = \vec{\nabla} \times \vec{V}[/itex]? This is the differential form of the integral equations you are used to - they are easier to use in general. Multiply it out and see what happens.

    Gradient is like this: [itex]\text{grad}V=\nabla V[/itex] and the other one is the divergence: [itex]\text{div}(\vec{V}) = \vec{nabla}\cdot\vec{V}[/itex]
    Last edited: Jul 23, 2012
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