Added mass & damping coefficient

Discussion in 'Boat Design' started by Paolo83, Jan 24, 2011.

  1. Paolo83
    Joined: Jan 2011
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    Paolo83 Junior Member

    Hello!

    I am studying the Strip-theory to derive the motion of a ship under the waves.
    The aim would be to determine the RAO's functions.

    :?: I wanted to know if anyone knows tell me a method to determine the added mass matrix and damping matrix for a simple geometry, such as a cylinder.

    thanks!
     
  2. Ad Hoc
    Joined: Oct 2008
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    Ad Hoc Naval Architect

    If memory serves, the added mass of cylinder is:
    rho x pi x rad^2

    Just check out anyt good fluid dynamics text book, such as "Fluid Dynamic Drag" by SF Hoerner
     
  3. jehardiman
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    jehardiman Senior Member

    Theory of Seakeeping by Korvin-Kroukovsky and published by SNAME has the complete deveration of the matrix and the Lewis factors for surface ships. PNA also has a compressed version of ToS in Vol III.
     
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  4. daiquiri
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    daiquiri Engineering and Design

  5. marknav
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    marknav New Member

    Besides previous posts, I know that Vougts made experiments to calculate the added masses for simple geometries and there are books about it. As idea try also to applicate the Morrison theory (approx empirical) for cylinder in a alternate flux, look for it, it might be interesting..
     
  6. Leo Lazauskas
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    Leo Lazauskas Senior Member

    1 person likes this.

  7. Paolo83
    Joined: Jan 2011
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    Paolo83 Junior Member

    Thanks!
    I'll watch it sure! :)
     
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