Kayak Tank Tests

Discussion in 'General Paddling Discussions' started by mick_allen, Nov 21, 2018.

  1. mick_allen

    mick_allen Paddler & Moderator

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    In the recent ‘Skeg Box Drag’ thread, mention was made of some tank testing way back in ’86 by Sea Kayaker mag. There were some factors shown that may still be of interest. Here's the first one: unfortunately limited file size upload keeps resolution a little low.
    this is the graph page:
    39.jpg
     

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    Last edited: Nov 21, 2018
  2. mick_allen

    mick_allen Paddler & Moderator

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    Here's the next one:
    with a great page
    37sm.jpg
     

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    Last edited: Nov 21, 2018
  3. mick_allen

    mick_allen Paddler & Moderator

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  4. mick_allen

    mick_allen Paddler & Moderator

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    To name drop a bit - the last two pdfs come from John [JKA here] with one page of the first lousy pdf that I made coming from the archives of the famous Paul Caffyn that John happens to be fairly well acquainted with! John states that he might be able to get better scans of the first set some time later.

    Incidentally, I was not happy with the graphic posted above, so I modified it a bit - if if helps:

    VelocityProfiles.jpg
     
  5. Roy222

    Roy222 Paddler

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    It would be very interesting if something like this could be repeated now, 30 years later. I suspect that more and more Navel Architects are using computer simulations.
    So, maybe, the best way to answer the skeg box question would be with a computer modeling on a small area around a Skeg box.
    But if laminar flow is already broken up, as suggested by the above graphic, then any measurement real or simulated would probably be mute. Because the real question, does the skeg box opening induce or increase turbulent boundary flow?

    Roy