Rolling chock alternate design for powerboat roll reduction

Discussion in 'Boat Design' started by makobuilders, Aug 11, 2019.

  1. makobuilders
    Joined: Feb 2009
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    makobuilders Member

    There was a discussion on another forum about rolling chocks for power boats, and this "staggered" design was brought up, as opposed to a traditional solid plate. Does anyone have any knowledge as to how much more (or less effective) this new design would be, compared to the traditional? Rolling Chock Staggered.png
     
  2. TANSL
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    TANSL Senior Member

    The more energy you lose in creating turbulence, the better.
     
  3. JSL
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    JSL Senior Member

    Interesting idea. More energy absorption might make it more effective. But:
    (a) disturbed water flow may?? cancel its effect, also cause water erosion, & create noise on the hull
    (b) more cleaning/maintenance re: marine growth & debris
    (c) more resistance. Okay for displacement speeds (slow).
     
  4. Squidly-Diddly
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    Squidly-Diddly Senior Member

    only advantage I could see is much better spreading of force on the hull, but how big an issue is that really? Only on a very weak hull that was subject to massive rolling.

    seems like it would add lots of drag. curious to know what sort of boat this was meant for.

    wouldn't it be better to add bilge-keels angle down about 45 degs that would also aid tracking and maybe beaching, grounding and prop protection?
     
  5. kapnD
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    kapnD Senior Member

    this Discussion begs for details!
    What hull, what target speed, what waters all very pertinent but missing facts here.
    IMO the necessity of such items points to a poor design, or application of the design, or owners who are not in tune with the wind and the waves...
     
  6. Deering
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    Deering Senior Member

    I’d expect it to be considerably more effective at roll dampening, but add a lot more drag during motoring. Why not go with a single perforated/slotted plate? It seems like that would accomplish the same thing without all of the appendage losses.
     
  7. makobuilders
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    makobuilders Member

    Deering, since mathematically modeling these two designs would be quite a task, I think it would be not too difficult to build two or three models, tow them sideways in a tank (or swimming pool) and measure the force required (ie - resistance). I'll keep this in mind.
     

  8. Deering
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    Deering Senior Member

    Good idea. You might want to tow them lengthwise while you’re at it to measure appendage drag.
     
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