how to get maximum GZ

Discussion in 'Stability' started by amjad357, Mar 26, 2012.

  1. amjad357
    Joined: Jul 2011
    Posts: 18
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: U.A.E Dubai

    amjad357 Amjad

    Dear All
    Good Morning,
    i have question.
    I have 135" fiberglass boat its already built but after the inclining experiment i can not get enough GZ.
    To get enough GZ i have to increase bouncy for next sister ship (model)
    is there any suggestion or trick to increase the GZ or bouncy??
    Kind regards
    Muhammad amjad
     
  2. Ad Hoc
    Joined: Oct 2008
    Posts: 6,124
    Likes: 358, Points: 83, Legacy Rep: 2488
    Location: Japan

    Ad Hoc Naval Architect

    Hi Muhammad,

    There are only 2 options open to you.

    1) Lower the KG...ie like adding ballast low down in the hull.

    2) Adding flair/tumble home to the hull side to increase the effective breadth.
     
  3. amjad357
    Joined: Jul 2011
    Posts: 18
    Likes: 0, Points: 0, Legacy Rep: 10
    Location: U.A.E Dubai

    amjad357 Amjad

    Thanks sir to reply me.
    I am agree with option 1

    I am planing to adding the weight in keel
    or
    I will move (underwater) bow area little forward.
    I hope it will me enough GZ
     

  4. Ad Hoc
    Joined: Oct 2008
    Posts: 6,124
    Likes: 358, Points: 83, Legacy Rep: 2488
    Location: Japan

    Ad Hoc Naval Architect

    No need to hope!

    If you have already done an inclining experiment, and you have the hull form in a hydrostatics program, you will have obtained your GZ curve. Since you know it is deficient, yes?

    Thus, it is a simple case of working out the location of the KG that will pass the criteria you're looking at. From then, you can do a simple moments check to see how much weight is required at what distance from the keel.

    Guessing is not required, simple calculations shall yield the answer. It may also surprise you too.
     
Loading...
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.