metacentric height

Discussion in 'Stability' started by BennyWailer, Mar 2, 2007.

  1. BennyWailer
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    BennyWailer New Member

    hi,
    I'm using Freeship to model a canoe. I want to find the metacenter at 15 deg of heel at a load. The program outputs stability cross-curves as KN*sin(theta)(ft).

    Is there a formula to I can use to find the metacenter.

    Cheers
     
  2. Guillermo
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    Guillermo Ingeniero Naval

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  3. BillyDoc
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    BillyDoc Senior Member

    That's a very good link, Guillermo, thanks!

    BillyDoc
     
  4. RANCHI OTTO
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    RANCHI OTTO Naval Architect

    Very usefull link! Thank you G.
     
  5. BillyDoc
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    BillyDoc Senior Member

    And another one I just stumbled onto, a low-level Navy course with pdfs of the chapters. Click on "Contents.pdf" and then ch01.pdf, etc. This is very basic stuff well explained. Just what I need most of the time!

    http://www.usna.edu/naoe/courses/en200/
     
  6. knowme
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    knowme Junior Member

    If I am right at 15 deg heel your metacenter M will coincide with your N. Hence you can find your metacenter from cross curves of stability. If I am wrong somebody correct me please.
     
  7. Guillermo
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    Guillermo Ingeniero Naval

    Nope. Have a look at the attached figure.
    Just a clue: KN = KM * sin θ ;)
     

    Attached Files:

  8. EAP
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    EAP Junior Member

    Mr G,
    Something Dosent Jive Between The Diagram You Posted And The Kn*sin(theta) Given In The Cross Curves Cals Of Freeship. Actually The Diagram Makes Sense To Me, What I Dont Understand Is What The Vertical Axis Of The Freeship Diagram Is Telling Us. It Seems That The Freeship Diagram Should Either Say Kn -or- Km*sin(theta) As Giving The Righing Lever.
    Any Thoughts???
     

  9. Guillermo
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    Guillermo Ingeniero Naval

    Could you post the Freeship diagram, please? I do not use that program. Maybe it's a typo or a diferent meaning of notation there. Have you gone through the manual?
    Righting lever GZ is equal to KN-KG sin(theta) in the notation I'm used to.
    Cheers.
     
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