Complex bowsprits on reversed bows

Discussion in 'Boat Design' started by John Rivers, Oct 4, 2022.

  1. John Rivers
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    John Rivers Junior Member

    Does anyone know the name of this type of bowsprit? And/or the inverted concave on the hull of reversed bows above the waterline? Or any structural analysis on this type of design?
     

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  2. John Rivers
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    John Rivers Junior Member

    I'm thinking of utilizing them as a critical line on the hull for when reversed bows dig deeply and to create a bowsprit/splash guard in the bowsprit from reversed bow overspray.
     
  3. Milehog
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    Milehog Clever Quip

    Bifid bows on a mono or multi hull?
     
  4. John Rivers
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    John Rivers Junior Member

    I'm looking at making them for a trihull. Thanks!
     
  5. Milehog
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    Milehog Clever Quip

    A bi tri?

    Sorry.

    I suspect it could act as a brake when the ama pierced a wave. Interesting concept.
     
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  6. John Rivers
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    John Rivers Junior Member

    I understand it's got lots of problems, but my thinking is to slice through small waves, but if it happens to dig deep there is a righting function from the concave set back from the bow a good bit. I'm also looking at trying to lower overspray from the reversed bow as it will be on a smaller trimaran styled holopuni kayak trimaran. I feel the holopunis designs are not optimized and are more of ancient culture appropriation. Another thought is a pitch poling correction mechanism in the hull when pitch poling reaches a critical mass, the hull pulls the reversed bow out of the water quickly.

    It's also to be used for going out and coming g in from 6' swells so as to cut through going out and prevent pitchpoling while coming in and riding a swell like holopunis.
     
    Last edited: Oct 4, 2022
  7. John Rivers
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    John Rivers Junior Member

    Oh I see now. The extreme braking would also have to be balanced. Perhaps a multi step triple concave serration such that the concave is repeated down the mid part of the front of the hull and becomes larger each step. I'm getting into regenerative engineering and would be interested how machine learning solves this problem in hull and bow design.
     
  8. gonzo
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    gonzo Senior Member

    You don't need machine learning. Humans can learn faster and better.
     
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  9. John Rivers
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    John Rivers Junior Member

    I agree. They only know the levels of variables the operator can design, but have increased efficiency in design occasionally.

    Right now I'm looking at the x bows and possibly designing a stepping concave on the hull. Giving certain strength and float criteria a program can give a few possibilities if one doesn't know where to start. I like what one guy said in here about reverse engineering being easier then engineering from scratch.
     
  10. Kayakmarathon
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    Kayakmarathon Senior Member

    The picture was interesting, so I visited Lobanov Design too see more. The Phoenicia is very artistic. The tumblehome cross section loses righting torque quickly as the hull heels in a hard turn or tack. This is a problem with the USS Zumwalt class destroyer, which uses only engines. The length to beam ratio looks to be relatively high, so the tall masts need a heavy keel to stay upright when cruising at a full speed. The skylight looks strong in the fore/aft axis, but very weak in the beam axis. Placing the masts at the intersections of the skylight's main longitudal and lateral frame members would be an improvement. The netting on the bowsprit wont stop waves from coming onto the deck in high seas. This luxury yacht would be best sailed in light conditions for safety reasons.
     
  11. jehardiman
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    jehardiman Senior Member

    You understand there is nothing real about the illustration (I will not justify it with the term "design")? A quick inspection shows many physical and engineering impossibilities; it is nothing more than a piece of imaginary 3-D artwork. FWIW to answer your questions: 1) there is no bowsprit (i.e. it supports no rigging or spars), those are trailboards (historically often open between them and used for the heads). 2) the forced perspective, ram bow, lateen rig, and extreme skeletonized tumblehome are conspicuous choices to evoke a exotic mediterranean feeling of an updated Greek trireme. 3) while a structural analysis and material selection could be done, I have doubts because it does not look like the simple hydrostatics to the (nominally imaginative) sail loads. And, oh yeah, the place for the Captain to stand and look "Captain-ey".

    EDIT : X-post with Kayakmarathon...similar but different, so I'll leave it.
     
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  12. John Rivers
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    John Rivers Junior Member


    Tha KS for you're overview. Some interesting points. I realize it's a concept drawing. I also realized open nets won't stop green water, but I'm looking more for overspray blocking.
    I'm thinking of a bowsprit for anchoring and for possibly to incorporate it into the stays of the build, but would mostly be for overspray guards. Things are still up in the air before I start building in solidworks.
     
  13. John Rivers
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    John Rivers Junior Member

    Today has been hugely rewarding in my bow/hull research. I'm looking at going with a modified thunderbird 2 center hull and asymmetric orca bows for the amas. Will be deep diving with the basic plans into solidworxs and Matlab soon.
     

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  14. Squidly-Diddly
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    Squidly-Diddly Senior Member


  15. Skyak
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    Skyak Senior Member

    "Fictitious"
    There is nothing connected to the sprit, so it isn't a sprit. Better term would be "pulpit". The hull is an artist interpretation of "wave piercing".
     
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