Controllable Pitch Propeller for lower power & electric motors

Discussion in 'Props' started by kistinie, Jan 2, 2010.

  1. kistinie
    Joined: Aug 2007
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    kistinie Hybrid corsair

    What are the available CPP solutions for the 1 to 30KW ?

    Application could be for ICE engine or Electric Motor/Generator

    Any products ?
     
  2. Fanie
    Joined: Oct 2007
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    Location: Colonial "Sick Africa"

    Fanie Fanie

    Hi Richard,

    I disagree. I think this could be the perfect prop for just such a motor.

    Let's just say you have a constant speed motor of which the speed cannot be varied, then the CPP would be the ideal prop, and solution for speed control.

    Don't discard the suggestion because you think it doesn't exist.

    Let me correct one thing - NOT an electric motor, but the speed of the 'motor' cannot be varied..

    Richard send me an e-mail to fanie at faze .co .za
     
  3. apex1

    apex1 Guest

    Well I am not aware of such a setup, and I do´nt see any sense in it.

    El propulsion is not uncommon and has its merits. But the combination is just nonsense.

    And why would one look for a constant speed motor / engine ? Just to complicate a simple solution?

    No, sorry, nonsense!
     
  4. kistinie
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    kistinie Hybrid corsair

    Short memory, bird name in each sentence you say...
    What a funny bird you are APEX !

    Please answer old questions before, and one time is enough :)) http://www.boatdesign.net/forums/hy...l-hybrid-applications-30289-3.html#post320293

    Then, please look at this nonsense generator powered by LEROY SOMMER research lab available and using a CPP

    http://www.wattandsea.com/

    How can you forget facts you perfectly know for so long... Are you here paid to help us forget and troll all propulsion innovation ? Are you doing a kind of lobby ?

    ALL industrials electric pods are CPP
     

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  5. apex1

    apex1 Guest

    Its senseless.

    once the lunatics have taken over the asylum, no sensible discussion can survive.

    Now we are talking 100.000 tons passenger ships.............. where the props are just adjustable btw.
     
  6. Fanie
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    Fanie Fanie

    Ok Richard, I too can sense your frustration.

    Could I suggest you steer us other idiots to remain within the borders of your cryteria then please, if you do not want any variation outside of this.

    I don't think the idea of CPP's are to be single purpose down the narrow line application alone and ban any other possible apps.

    While they do have an already fixed application, some of us feel that they may possibly be used for other applications also, and are looking up at you for advice and guidance about this.

    Please explain why -
     
  7. kistinie
    Joined: Aug 2007
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    kistinie Hybrid corsair

    Adjustable :)) Controllable ? ok, no more CPP if you prever to call it like this ! APP... for APPEX !! :))
    Lunatic you said :))


    WATTANDSEA is 500W to 1KW pod maid for a 6 T ship and is a TRUE CPP
    Pitch is oiled controlled.
    For 1 passenger !


    As a conclusion :
    CPP is Perfect for a small boat electric pod.... perfect for big boats, and... nonsense between ?

    Illogical captain APP ...EX !
    :)
    Illogical.


    To return to CPP tech :
    Can a CPP be just a progressive pitch propeller a kind of passive CPP but without moving parts ?
    Such solution was used with carbon blades deformed by torque
    Any other designs availlable ?
     
  8. apex1

    apex1 Guest

    Well thats simple Fanie.
    The El. motor has no problem to operate at any rpm within its designed range, and provides full torque at any rpm. It is also easy to run a El. motor in either direction. Therefore a controllable pitch propeller has little or no advantage.
    The Diesel engine needs sufficient load to operate economical and healthy. A fixed pitch prop does provide that at one rpm only. Rarely a boat can be operated at a fixed rpm. When trolling at low speed as a fisherboat does, or when cruising at reduced power, as a passagemaking vessel does, the engine is critically underloaded with a fixed prop. Thus shortening the servicelife and increasing the specific consumption to a senseless extend.
    The CPP allows for a sufficient workload of a Diesel engine at almost every RPM, by adjusting the pitch. This saves fuel and keeps the engine in a wealthy condition.
    As a welcome sideeffect it gives one the freedom of having some extra power installed to be prepared for the really nasty conditions, without the need to operate the engine in a expensive power range at calm conditions.

    Hope that was clear enough.

    Regards
    Richard
     
  9. kistinie
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    kistinie Hybrid corsair

    An electric motor is more linear than ICE
    But saddly, an electric motor is not enough linear on the full rpm range you will need when regenerating and motoring.

    CPP offers the needed torque conversion as well as reversing of the blades
     
  10. kistinie
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    kistinie Hybrid corsair

    CPP are products that need a little more initial investment.

    The over cost is fully paid by efficiency rise.

    So most of the time...

    It will lead you to keep your boat for a longer time, consuming less new motor, less fuel...

    What does the boating and oil industry think of this last sentence ?
    Can it be correlated with the lack of CPP for consumer market ?

    :))
     
  11. kistinie
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    kistinie Hybrid corsair

    This nice talk about AUTOPROP is virtual as clueless.
    Not a single power curve are compared or showed

    Second, i look for efficiency curve that suits my needs, so if prop is 8% bigger or smaller...

    In deep !

    :))
     
  12. kistinie
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    kistinie Hybrid corsair

    Narrow, and probably, inexistent, or much too heavy for under 30Kw and electric applications.
     
  13. Marco1
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    Marco1 Senior Member

    So we have the believers and the deniers, as one would expect.

    But there seem to be many who think there are no CPP for smaller boats.

    There is Sabb for one, there may be others.
    Who knows of a small CPP supplier for engines under say 50HP or even under 100HP?
     
  14. kistinie
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    kistinie Hybrid corsair


    As answers to this question are rare why not look for an alternative propeller design to CPP, giving a "as constant as possible" torque ?
     

  15. kistinie
    Joined: Aug 2007
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    kistinie Hybrid corsair

    For serious low power boaters, there is seriously nothing or close to, on the CPP segment. Should i understand you are unhappy with that, just like us ?
     
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