What is the meaning of trim equilibrium for a ship?

Discussion in 'Boat Design' started by xichyu, Apr 12, 2016.

  1. xichyu
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    xichyu Junior Member

    What is the meaning of trim equilibrium for a ship?
     
  2. DCockey
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    DCockey Senior Member

    Is this a question from an assignment or test?
     
  3. xichyu
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    xichyu Junior Member

    I am a student, I am learning ship theory now
     
  4. gonzo
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    gonzo Senior Member

    Do you mean how to calculated the trim of the vessel as you change the load? That is, where is the waterline?
     
  5. xichyu
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    xichyu Junior Member

    I think so
    Thanks
     
  6. Heimfried
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    Heimfried Senior Member

    I don't know if it would be helpful, but may be. Try it, if you want.

    You can play with the centers of gravity and bouyancy, shift load and look at the change of trim and heel.

    http://www.bootsphysik.de/rechner/bootx.php

    First click button "English" at the first line right.
    Then "show legend",
    input at "mass to relocate" 300, TAB
    input at "longitudinal" 300, TAB
    click "apply relocation"
    the red dot (CG) has moved a bit

    click "find equilibrium" (bottom)
    (answer comes slowly)
    shown trim angle is 0.5 deg.
     
  7. xichyu
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    xichyu Junior Member

    Thanks!
    Can I input a model made by myself?
     
  8. Heimfried
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    Heimfried Senior Member

    Sorry, you can't.

    (But if you are able to provide a csv-file with appropriate data of a boat hull, I could install it.)

    There is an other site with a few different frames to choose.
    But it deals only with heel, not with trim.

    http://www.bootsphysik.de/rechner/bootxp3.php
     
  9. xichyu
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    xichyu Junior Member

    If it can not conveniently input a model. I do not think it can be used extensively
     
  10. Heimfried
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    Heimfried Senior Member

    You are right,
    but the site is not to calculate the behaviour of user's boat.

    It is to show exemplary the things about stability, heel and trim.
    It is to learn about and to develop a sense to boat hydrostatics.
     

  11. xichyu
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    xichyu Junior Member

    I got it, Thanks all the same!
     
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