How much Push or Pull do you need ?

Discussion in 'Propulsion' started by Canada Bob, Dec 22, 2011.

  1. Submarine Tom

    Submarine Tom Previous Member

    "I guess that {if you are interested enough Tom} we could exchange a simple NDA then on the understanding of "Confidentiality" I could raise the veil so to speak."

    Exactly what I had in mind with the Personal Message idea...

    -Tom
     
  2. Canada Bob
    Joined: Apr 2009
    Posts: 64
    Likes: 2, Points: 0, Legacy Rep: 22
    Location: Halifax, Nova Scotia

    Canada Bob Junior Member

    We'll do that Tom, the signal to noise ratio in here aint worth the bother.
     
  3. truecougarblue
    Joined: Dec 2011
    Posts: 26
    Likes: 2, Points: 0, Legacy Rep: 32
    Location: cali

    truecougarblue Junior Member

    Apology

    A heartfelt apology for my posts, all of them. They will be deleted.

    My first post was a genuine attempt to help. Math errors and notation errors and conversion error and all, I apologize for posting in haste (to get to the dinner table no less).

    I promise to do better in the future.

    BTW, flat plate drag has everything to do with your question, if I understand it correctly, just sayin'...
     
    1 person likes this.
  4. Canada Bob
    Joined: Apr 2009
    Posts: 64
    Likes: 2, Points: 0, Legacy Rep: 22
    Location: Halifax, Nova Scotia

    Canada Bob Junior Member

    A heartfelt apology for my posts, all of them. They will be deleted.
    Ah, well, we all have bad days, apology accepted...

    My first post was a genuine attempt to help. Math errors and notation errors and conversion error and all, I apologize for posting in haste (to get to the dinner table no less).
    Looks like I may well have initially missed your first post, due to the season, visiting folks and folks visiting here, not to mention that the topic sort of grew a life of its own rather quickly, and I wasn't exactly keeping up.

    I promise to do better in the future.
    Don't we all ;-) no hard feelings, just one of those things...

    BTW, flat plate drag has everything to do with your question, if I understand it correctly, just sayin'...
    Err, well, there isn't any plate involved at all, I was just trying to give a graphic of the principle, in fact, there's essentially no moving part at all, so there's no drag whatsoever, it's just a "method" of applying a force to the water to propel the boat along.
     
    1 person likes this.
  5. Canada Bob
    Joined: Apr 2009
    Posts: 64
    Likes: 2, Points: 0, Legacy Rep: 22
    Location: Halifax, Nova Scotia

    Canada Bob Junior Member

    Thanks for the above MechaNik, valued and appreciated, particularly the equation re pressure, area and Newtons.

    As for circular motion there's none involved so that should make the calculations and considerations a lot easier.
     
  6. Mr Efficiency
    Joined: Oct 2010
    Posts: 8,553
    Likes: 500, Points: 113, Legacy Rep: 702
    Location: Australia

    Mr Efficiency Senior Member

    Bob, just make the bloody thing and see how it turns out, it is not possible for people to give a meaningful opinion on something, if they have no idea how it functions. Sure, you don't want to reveal your secret, but the flip side of that is 'help' becomes problematical, at best. Good luck with it, hope you can report back with some data on how it performs. :D
     
  7. Canada Bob
    Joined: Apr 2009
    Posts: 64
    Likes: 2, Points: 0, Legacy Rep: 22
    Location: Halifax, Nova Scotia

    Canada Bob Junior Member

    Forgive me for raising your ire Mr E, but I'm the sort of bloke who "measures twice and cuts once". In this case the measuring was an attempt to get some idea from folks in here as to what the scale/size/area of the force that might be needed, before I built "the bloody thing". I'm amazed that folks might think that's it "not possible" to respond to that, oddly enough MechaNik has {in one} explained that principle without the need to insult the enquirer.

    I guess there really is a Galileo syndrome, where if you dare to think what others can't conceive of the pack starts to howl.
     
  8. tunnels

    tunnels Previous Member

    push ?? pull ??pulling ??pushing ??very confusing !!

    :confused:You can push more than you can pull its a well known fact ,so pushing is in but to get the pusher to work and push you sometimes have to pull the dangly bit at the top , after you pulled that the pusher should start to push but if its a small pusher it could become a puller as some small pushers rotate 180 gegrees and become pullers !! so now the pusher is a puller and its not as efficent at pulling as it was when it was a pushing ! so to change the puller to a pusher again you need to spin the puller thing back to where it was when it was a pusher and then your puller becomes a pusher again !! simple ah !!
    With your wee puller that was a pusher needed to have a puller to pull the dangly pull thing to start it you can now rev up and be on your way to where ever you want your universal puller, pusher thingie to take you any where you want to go !. :p
     
  9. Canada Bob
    Joined: Apr 2009
    Posts: 64
    Likes: 2, Points: 0, Legacy Rep: 22
    Location: Halifax, Nova Scotia

    Canada Bob Junior Member

    Hello Tunnels, thanks for your input and the good humour, appreciated.
     
  10. Mr Efficiency
    Joined: Oct 2010
    Posts: 8,553
    Likes: 500, Points: 113, Legacy Rep: 702
    Location: Australia

    Mr Efficiency Senior Member

    No ire raised here. :D It was explained early on how to get a reasonably accurate idea of the resistance you have to overcome, but I doubt anyone has any idea what you are proposing to use as the "drive", without a rough outline of it's basics. I have a picture in my mind of an umbrella-like attachment on the end of a shaft that moves back and forth, opening on the power stroke, closing on the forward stroke. I hope you got somethin' better than that !
     
  11. tunnels

    tunnels Previous Member

    HAVE A GOOD NEW YEAR IN 2012 FOLKS AND KEEP ON PUSHING FOR A BETTER FUTURE !! BECAUSE 2010/11 WAS PULLING US DOWN :D:p
     
  12. Canada Bob
    Joined: Apr 2009
    Posts: 64
    Likes: 2, Points: 0, Legacy Rep: 22
    Location: Halifax, Nova Scotia

    Canada Bob Junior Member

    OK, let's get onto a better understanding, of each other and of the concept.

    First of all there are no mechanical parts to the system, no umbrellas, no push plate, nothing that you might call or {immediately} recognise as a moving part, yea, I know, it gets stranger by the minute, and to some would seem therefore to be frivolous or fanciful, but to balance that {if I can} no one has put more time into this thread than I have, so if I was just shooting the breeze it would be my own time that I'd be wasting.

    My original enquiries were aimed at figuring out how large this "device" would need to be to provide adequate propulsion, doing that by finding out what force would be needed {for a small craft} to start it moving. From that I would then know if I could scale up my "engine" to produce such a force, kind of simple as that...

    In response to folks "not having any idea of how the drive is produced" well, that don't matter really does it, all I need to know is how much "drive/force" is required. My guess is that it don't matter at all what produces it, could be steam {as an example} the only question really is, as asked previously how much force is needed, rather than focus on what "mysteriously" seems to produce it...

    To reiterate, there are no mechanical or {as we might commonly consider} any moving parts involved.
     
  13. Submarine Tom

    Submarine Tom Previous Member

    Look, don't push it, okay?

    Or, are you pulling my leg...?

    -Tom
     
  14. Submarine Tom

    Submarine Tom Previous Member

    Okay, funny haha's aside.

    The paddling canoe provides a great example of how much force is needed to move a canoe.

    Any Canadian worth his/her salt has paddled a canoe and knows exactly how much force is required.

    -Tom
     
    1 person likes this.

  15. hoytedow
    Joined: Sep 2009
    Posts: 5,594
    Likes: 252, Points: 93, Legacy Rep: 2489
    Location: North of Cuba

    hoytedow Wood Butcher

    The more pull you have the less pushy you need to be.
     
    1 person likes this.
Loading...
Forum posts represent the experience, opinion, and view of individual users. Boat Design Net does not necessarily endorse nor share the view of each individual post.
When making potentially dangerous or financial decisions, always employ and consult appropriate professionals. Your circumstances or experience may be different.