Would a bulbous bow below the waterline help

On Tue, Nov 30, 2021 at 9:31 PM schiller via CnC-List <cnc-list@cnc-list.com>
wrote:

> No, but we did add "turbulators" to the tail section of the GBU-24 Bunker
> Buster Guided Bomb to break up the boundary layer between the bomb body and
> the wing section, causing turbulent flow over the wings.
>
> Neil Schiller
> 1983 C&C #5-3, #028, "Grace"
> Whitehall, Michigan
>
> On 11/30/2021 6:05 PM, Graham Collins via CnC-List wrote:
>
> Indeed.  You don't see dimples on the wings of aircraft, for a good
> reason...
>
> Graham Collins
> CS 36T
>
> On 2021-11-30 3:50 p.m., Dreuge via CnC-List wrote:
>
>
> On Nov 30, 2021, at 1:47 PM, Doug via CnC-List <cnc-list@cnc-list.com>
> wrote:
>
> This is the reason golf balls have dimples. Aides in better flight, less
> resistance.
>
>
>
>
> Yes (if spinning) and No (as it adds lateral resistance).
>
> Going with a smooth surface is the overall best approach as it promotes
> smooth laminar flow.   There are times when a ruff surface helps maintain
> laminar flow.  For example, the dimples on a golf ball create a thin
> turbulent layer which drags air and helps keep the lamina flow closer to
> the surface behind the ball.  The dimples add resistance to the flow but
> reduces the air wake behind the ball which reduces the overall drag force.
> The laminar flow around a smooth ball does not wrap around the back of the
> ball as well and leaves a larger wake.  The larger the wake, the larger the
> drag.
>
> I think it would be foolish to add dimples or an orange peel bottom,
> unless you have the resources to model and measure the effect for a
> particular boat.  Maybe adding some aft ruffness as the hull as turns
> inward, but this will strongly depend on the individual hull shape and
> likely have a positive effect at high water speeds (and a negative effect
> at low).   Of course, a great way to reduce one's wake is to foil.
>
> Most may recall that dimples of a spinning golf ball help in another and
> bigger way by providing lift(i.e. aids in better flight).  The spinning
> dimples drag air towards incoming flow and drag air away from the flow on
> the opposite side causing a high/low pressure difference (i.e.  lateral
> lift force).   This latter effect has not yet been exploited by sailors.
> Who knows, maybe we’ll see a spinning belted keel in the future driven by
> Kiwi’s pedal power.
>
>
> -
> Paul E.
> 1981 C&C Landfall 38
> S/V Johanna Rose
> Fort Walton Beach, FL
>
> http://svjohannarose.blogspot.com/
>
>
>
>
>
> Thanks to all of the subscribers that contributed to the list to help with 
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>
>
> Thanks to all of the subscribers that contributed to the list to help with 
> the costs involved.  If you want to show your support to the list - use 
> PayPal to send contribution --   https://www.paypal.me/stumurray  Thanks - Stu
>
>
> Thanks to all of the subscribers that contributed to the list to help with
> the costs involved.  If you want to show your support to the list - use
> PayPal to send contribution --   https://www.paypal.me/stumurray  Thanks
> - Stu

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send contribution --   https://www.paypal.me/stumurray  Thanks - Stu

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