Elliptical Submarine Hulls

Discussion in 'Boat Design' started by Asleep Helmsman, Jan 16, 2010.

  1. haru
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    haru Junior Member

    You mean on the same horizontal plane.
    If not on the same plane I would bet on formation of vortices on the y-z-plane (math). This would be bad for altitude control.
     
  2. Asleep Helmsman
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    Asleep Helmsman Senior Member

    Here's a general Question.
    How much of an increase in drag would a surface piercing bow configuration (sharp leading edge)cause while diving.
     
  3. haru
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    haru Junior Member

    If the body stays roughly the same while the bow is exchanged, then depending on the L/D ratio there could be less drag. But if it's a short body then there can more more drag. Generally, it's said there is no gain from a piecing bow for a submarine.
     
  4. Asleep Helmsman
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    Asleep Helmsman Senior Member

    Other than being underway on the surface, and station keeping while surfaced. The ballance is how much cost when submerged.

    However if station keeping is a requirement, than you have to do what ever is nessisary.
    the L/D is 8 to 1
     
  5. playmaker
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    playmaker Junior Member

    Hi,
    is there anyone know about calculate a submerged body resistance-power prediction method... It can be simple..
     
  6. daiquiri
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    daiquiri Engineering and Design

  7. haru
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    haru Junior Member

    prismatic coefficient Cp: no change
    Cp extreme: up to 5% less
     
  8. Asleep Helmsman
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    Asleep Helmsman Senior Member

    Thank you.
     
  9. gonzo
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    gonzo Senior Member

    I think when you mix wave making resistance with uderwater body resistance the discussion looses meaning. They are two different things.
     
  10. Asleep Helmsman
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    Asleep Helmsman Senior Member

    Separate from drag there are other condition that must be met.
    While surfaced, seakeeping, and station keeping are paramount. Depending on mission parameters these two requirements could easily override drag restrictions when submerged. At the very least they must be considered.
    Certainly for surface boats, a bow that pierces the water is generally desirable. So the question is; what method would you use to determine the least impact on submerged drag?
     
  11. playmaker
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    playmaker Junior Member

  12. Asleep Helmsman
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    Asleep Helmsman Senior Member

    I finished the hydrodynamic design of the robotic submarine. We changed the code name from Tad pole to String Ray.

    In its current evolution, the outer hull is not a pressure hull. We will see if that holds up to cyclical design efforts.
     
  13. haru
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    haru Junior Member

    Congrats.
    So do we get to see a race? :)
     
  14. Asleep Helmsman
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    Asleep Helmsman Senior Member

    Not likely to be in any races.
     

  15. Asleep Helmsman
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    Asleep Helmsman Senior Member

    Elliptical UUV Submarine Hull

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    Copyright © 2010 Clear Lake Oceanographics
     
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