Initial Stability Calculation Error in Freeship

Discussion in 'Stability' started by ricardo.halfeld, Mar 18, 2009.

  1. ricardo.halfeld
    Joined: Mar 2009
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    Location: Rio de Janeiro

    ricardo.halfeld New Member

    I was setting the shape of my boat's hull in Freeship v2.6, a catamaran by the way, and I realized my initial longitudinal stability (KMl) was negative while my transverse stability was ok. So I opened the design hydrostatics and saw the that the longitudinal waterline inertia was also negative, thus making my KMl negative.

    Is this a known issue for cats in this Freeship version?
     
  2. marshmat
    Joined: Apr 2005
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    Location: Ontario

    marshmat Senior Member

    Hi Ricardo,

    Yes, this is a common problem when modelling a catamaran in Freeship. I haven't found any way around it- although, to be fair, I have neither the coding skill or the time to go into the source code and find the problem. For cats, I usually work with only one hull in Freeship, then turn it into a cat in something else- usually Rhino.
     
  3. ricardo.halfeld
    Joined: Mar 2009
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    Location: Rio de Janeiro

    ricardo.halfeld New Member

    Thanks Matt.

    Do you know if DelftShip calculates it any better?
     
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