Kayak stability

Discussion in 'Stability' started by lost, Jul 30, 2017.

  1. TANSL
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    TANSL Senior Member

    In any naval software it is possible to simulate, and it is normal to do so, loading conditions in which the total CoG of the ship is initially outside the longitudinal plane. This produces an initial equilibrium situation with a given heel. From there, the stability curves GZ and DN are calculated for that condition.
     
  2. gonzo
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    gonzo Senior Member

    This is not a load, but a person reacting to changes in stability. Traditional kayaks are supposed to have very little initial stability. Otherwise, classic maneuvers, like the eskimo roll would not be possible. What naval software is there available that can model the kayak handling of an expert?
     
  3. TANSL
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    TANSL Senior Member

    I would rather not comment on this technical differentiation:p.
    But I insist, as I know several naval architecture programs, any software (or major programs) for these calculations is (or should be) prepared for studies of this type, if the user has sufficient knowledge of naval architecture and on the software he is using.
     
    Last edited: Aug 4, 2017
  4. gonzo
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    gonzo Senior Member

    Can you name the programs that take into consideration the movement of the crew in response to sea conditions, when the crew constitutes 60-70% of the total displacement?
     
  5. TANSL
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    TANSL Senior Member

    (Whatever the % of the total crew represents. That is anecdotal. The program never asks for the type or name of the weight.)
    Only those programs that I know, for having worked with them:
    • Foran
    • Hydromax
    • ARQN
    • DefCar
    But also, as I said, you have to know about naval architecture and you have to know how to use the software. The software does nothing that the user does not know how to ask.
    Other software developers could complete this list.
     
  6. gonzo
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    gonzo Senior Member

    The % is not anecdotal, but a measured fact. Are you saying that those programs calculate human response to the environment?
     
  7. TANSL
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    TANSL Senior Member

    That the weight is that of the crew or the one of a stone on the seat will not change in any way the problem to study.
    And NO, human response to environment can not be calculated by any existing software. Predictions can be made about the human response to certain stimuli but, as we all know well, these predictions fail much.
    The response of a ship to the environment, although not easy to obtain, is much more predictable than the human response. But also in this case it is estimates, more reliable, but estimates at the end. Do not think, for some of what I have said, that one can accurately calculate the behavior of a ship. The theory of the ship is not an exact science. One of the first problems with the designer is to build a model (not just talking about 3D virtual models) that is sufficiently close to the reality of the problem to be studied. But the better this model, the better the response will be. That is why, among many other factors, the designer and his knowledge are as important, more important in fact, than the software used. The software, I would not need to explain, is just a tool. Totally nimble tool in inexperienced hands.
     
  8. gonzo
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    gonzo Senior Member

    That was my point. That in a vessel where the crew is several times heavier than the hull/deck, there is no existing software that can be used to calculate stability.
     
  9. TANSL
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    TANSL Senior Member

    How do I need to explain to you that the software for the ship's calculations does exist? You just need to know how to use it.
    The weight of the crew in relation to the weight of the hull is NOT a determining factor of the existence or not of the software.
     
  10. gonzo
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    gonzo Senior Member

    In #21 I asked you if you :" Are you saying that those programs calculate human response to the environment?" and you responded: "And NO, human response to environment can not be calculated by any existing software." Which is it, because you are totally wrong in saying : "That the weight is that of the crew or the one of a stone on the seat will not change in any way the problem to study."
     

  11. TANSL
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    TANSL Senior Member

    All right, all right, you're right. At the end of the day, what do I care.
     
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