Deep V catamaran optimisation...

Discussion in 'Powerboats' started by CpDigriz, Apr 14, 2015.

  1. CpDigriz
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    CpDigriz Junior Member

    Hello. I have this task of designing a 2mx2mx2.5m dimension catamaran with deep v demi hulls and small chines for lift. Thing is, I am a burried under piles of information on how to do it. Is there some source (book or site) that could help me out with things like calculating the trim angle, deadrise angle, optimal size of chines, lift, drag and the length to width ratio of hulls.

    Any help would be much appreciated!
     
  2. gonzo
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    gonzo Senior Member

    Question #1: is it a power or sailboat?
     
  3. Mr Efficiency
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    Mr Efficiency Senior Member

    2mx2mx2.5m ? Is that correct ? Sounds more like a hen-house !
     
  4. Marmoset
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    Marmoset Senior Member

    Chooka-Marian?


    Barry
     
  5. Manfred.pech
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    Manfred.pech Senior Member

  6. CpDigriz
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    CpDigriz Junior Member

    It's a power catamaran. One engine only made to carry up to 200kg of cargo by remote controll.
     
    Last edited by a moderator: Apr 15, 2015
  7. CpDigriz
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    CpDigriz Junior Member

    Yea its a wee one, but that's not more than enough for me =D
     
  8. upchurchmr
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    upchurchmr Senior Member

    If it is a power cat, requiring a relatively high load carrying capability, you should not be using a deep V.

    How about a square underwater section, as narrow as possible on each hull.

    The 2.4M total width will probably cause bow wave interference between the hulls.

    I have a 11' x6' total width, with 12" wide hulls with round bottoms. It only carries the 100# boat and a 250# person. When it was 4" total width it had significant interference drag.

    Do you have a speed requirement for the power?
     
  9. nzclipper
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    nzclipper Junior Member

    Have a look at james bretts unicat design. Not 2m wide, but about 2.5 long, cat configuration, shallow v, not deep, turn into barge when loaded up.
     
  10. CpDigriz
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    CpDigriz Junior Member


    I read that V hulls decrease the slapping and make it better to steer. Also it;s going to swin in easy waters with waves up to 30cm only.

    I dotn have speed requierment per say, but i want it to go as fast as possible and be as efficient as possible.
     
  11. upchurchmr
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    upchurchmr Senior Member

    Will you care about "slapping" if this is a RC boat?
    What do you mean by slapping? Do you think this is going to slow down the boat?

    You need to really define your requirements.
    If you want it as fast as possible it needs to be planning with a big motor. Is that realistic for your design?

    The deep v hull in post 5 should make it track well, but be more difficult to manuver.
     
  12. CpDigriz
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    CpDigriz Junior Member

    I was afraid slapping would slow it down...are you saying that it wont do much for a small ship like this?

    I wish i could do hydro foils, but there is simply no time. I want it to be planning though with small chines on the side for lift.
     
  13. upchurchmr
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    upchurchmr Senior Member

    I'm not a real powerboat guy.
    But small chines probably won't support much unless you go really fast.

    Most power boats I see are not deep V.

    Perhaps you can provide a drawing so the real power boat guys can see what you actually mean.
     
  14. Mr Efficiency
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    Mr Efficiency Senior Member

    What is needed here is a detailed shopping list of what this contrivance is intended to do.
     

  15. CpDigriz
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    CpDigriz Junior Member

    It's intended to carry a load of 200kg in a lake with waves of up to 30cm for a distance of around 0.5km with some manoeuvering with biggest focus on speed.
     
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