Does duration of slam scale with Froude?

Discussion in 'Boat Design' started by floating, Oct 27, 2015.

  1. floating
    Joined: Jun 2009
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    floating Junior Member

    I would love confirmation of my following assumption: the duration of a slam event scales with Froude scaling. So if I make a 1:10 scale model and slam is 0.01 seconds long, at full scale it would be 0.01*sqrt(10) = 0.03 seconds long.

    My colleague has pointed out: if you slam a flat plat and all areas of the plate register peak slam pressures simultaneously*, then slam duration should not scale with Froude scaling. *we don't know this to be the case.

    What do you think?
     
  2. gonzo
    Joined: Aug 2002
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    gonzo Senior Member

    Are you trying to narrow it down to only flat plates, or calculating heaving period?
     
  3. floating
    Joined: Jun 2009
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    floating Junior Member

    I am just focused on the duration of a slam event, i.e. how long high pressure is experienced when an object impacts the water surface. Does this duration increase if the object is bigger?
     

  4. jehardiman
    Joined: Aug 2004
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    jehardiman Senior Member

    No, see my post in the other thread.

    Actually, now that I think about it, Froude himself had an analogy about horses running on water....all they had to do was step very quickly and lightly.
     
    Last edited: Oct 27, 2015
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