Help Formula?

Discussion in 'Stability' started by Laranjo123, Jul 10, 2011.

  1. Laranjo123

    Laranjo123 Previous Member

    Do you have a formula for VCG VCB LCG LCB and period of rolling?
    Need pls thesis purposes.
    It would be great if you have ebooks to share cause i've been researching those formulas but the net does'nt have them. (i think)
    Thx in advance
  2. terhohalme
    Joined: Jun 2003
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    Location: Kotka, Finland

    terhohalme BEng Boat Technology

    Any naval architecture study book will do the job. For thesis YOU need to find them!
  3. MengWalton
    Joined: Jul 2011
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    Location: United Kingdom

    MengWalton Junior Member

    I have all of those, cant remember them all off the top of my head, i can remember some, but ill double check in my book tomorrow, and post them, if someone hasnt already put the formule down.
  4. Olav
    Joined: Dec 2003
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    Olav naval architect

    VCG = (∑mi * zi) / mtotal

    VCB = (∫z * A *dz) / V

    LCG = (∑mi * xi) / mtotal

    LCB = (∫x * A * dx) / V

    LCG = LCB for equilibrium

    A = sectional area
    mi = single mass
    mtotal = total mass = ∑mi
    V = displaced volume
    x = coordinate in longitudinal direction
    z = coordinate in vertical direction

    Concerning roll period you might want to have a look at this thread and make up your own opinion.

    Just out of curiosity: What subject do you study/write your thesis in? If it's anything along the lines of naval architecture I'd highly recommend to postpone your thesis and start it all over from the very beginning. These basics of hydrostatics are first year stuff.
  5. Laranjo123

    Laranjo123 Previous Member

    sir pls do post them i need more formulas( if you find them?) . Im going to get their average values....
  6. Laranjo123

    Laranjo123 Previous Member

    anyone who have formulas can post them here ^__^
  7. commodore
    Joined: Jan 2008
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    commodore New Member

    I don't want to be rude or offensive, but Olav already posted such formula:

  8. Laranjo123

    Laranjo123 Previous Member

    thx guys i have the book it's called parametric design by michael g parsons. I only got the chapter 11 of it. haha

  9. daiquiri
    Joined: May 2004
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    Location: Italy (Garda Lake) and Croatia (Istria)

    daiquiri Engineering and Design



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