How to obtain the maximum righting arm of a righting arm curves?

Discussion in 'Education' started by xichyu, Apr 12, 2016.

  1. TANSL
    Joined: Sep 2011
    Posts: 4,481
    Likes: 79, Points: 58, Legacy Rep: 300
    Location: Spain

    TANSL Senior Member

    It is unlikely, quite improbable that GZ curve has a flat area values. Unless you understand as "stability curve" anything else.
    A double humped curve stability can exist but is not "very common". It occurs mainly in ships with a forecastle deck that encloses much volume.
     
  2. xichyu
    Joined: Apr 2016
    Posts: 99
    Likes: 0, Points: 6, Legacy Rep: 10
    Location: Dalian,Liaoning,China

    xichyu Junior Member

    Oh,I forget the “ double humped stability curve” . Thanks
     
  3. gonzo
    Joined: Aug 2002
    Posts: 12,349
    Likes: 198, Points: 63, Legacy Rep: 2031
    Location: Milwaukee, WI

    gonzo Senior Member

    I meant to say "not very common"
     
  4. PAR
    Joined: Nov 2003
    Posts: 18,595
    Likes: 376, Points: 93, Legacy Rep: 3967
    Location: Eustis, FL

    PAR Yacht Designer/Builder

    Actually, when you accurately plot a stability curve, it can have a number of "bumps" in it. Typically when the side deck submerge, a flattening on the curve occurs, then when the cabin or deck structures start to submerge, the curve spikes up again. Depending on how you calculate the curve (many don't include deck structures) and the configuration of the deck, you can have a number of bumps.

    In small craft design, the curve is typically hull only, through 180 degrees. This is how I do small craft, knowing the actual AVS may be a bit higher, than the calculations show, but an error toward the higher side isn't a bad thing. On larger craft ,the deck structures have to be included, but not so much on a 22' sloop (as an example) with a small cabin on it's foredeck.
     
  5. xichyu
    Joined: Apr 2016
    Posts: 99
    Likes: 0, Points: 6, Legacy Rep: 10
    Location: Dalian,Liaoning,China

    xichyu Junior Member

    ha ha
     

  6. xichyu
    Joined: Apr 2016
    Posts: 99
    Likes: 0, Points: 6, Legacy Rep: 10
    Location: Dalian,Liaoning,China

    xichyu Junior Member

    Thanks!
    It is useful for me
     
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.