Jet Cavitation Issues on Prototype Hull

Discussion in 'Jet Drives' started by Hyperlite, Jun 13, 2020.

  1. Hyperlite
    Joined: Jun 2020
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    Hyperlite Junior Member

    That is one of the tests we are going to do, tie off the boat to a structure and ease into the throttle and see if it still cavitates. That should eliminate the hull design as the main culprit if it still cavitates.
     
  2. Mr Efficiency
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    Mr Efficiency Senior Member

    I guess with no forward motion, you are encouraging cavitation, somewhat, but seeing the thing is losing the plot without a lot of throttle application, then I think it is worth doing.
     
  3. Mr Efficiency
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    Mr Efficiency Senior Member

    If it is the hull, and aerated water, the only fix that comes to mind, would be a modified intake, that is running a little deeper, and not picking up air bubbles coursing along that flat, but there may be losses of fuel efficiency entailed in that, in "lifting" the intake water. Anyway, one thing at a time, hey !
     
  4. baeckmo
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    baeckmo Hydrodynamics

    Hi Hyperlite, I've just sent you a message via the forums contact function; welcome, hope it works that way. Like other professionals here, I guarantee the non-disclosure of your intellectual property, but since an important function of this forum is experience-sharing for our common benefit, I may seek your permission to lift specific issues of common interest into the forum.

    Brgds, /B
     
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  5. Alik
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    Alik Senior Member

    To me, it sounds like an USV, with slow patrol speed. We did such boats, yes jets are not normally designed to operate at such low speeds for continuous time.
    To come below cavitation line, we used 80% of manufacturer's cavitation limit and played with jet diameter. Note most of cavitation limits from manufacturers are too optimistic.
     
  6. Mr Efficiency
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    Mr Efficiency Senior Member

    The hull is not a conventional vee hull, which may be the wild card in the equation.
     
  7. Ad Hoc
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    Ad Hoc Naval Architect

    Too much speculation - insufficient facts.
     

  8. Mr Efficiency
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    Mr Efficiency Senior Member

    Did you see his illustration of it ?
     
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