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Re: Fluid stability?
By:Dave King
Date: 7/2/1998, 2:19 pm
In Response To: Fluid stability? (Karl Coplan)

My guess is that as the kayak's velocity increases so does the resistance to both intitial and secondary stability. Is it possible that the force of friction, increasing with velocity, makes it harder to tip over? I was thinking of a water skier and a windsurfer, both carving turns at speed; both unable to do the same things a slower speeds. It would seems that their initial and secondary stability increase in proportion to velocity. But, this is just a guess.

> While paddling home into a confused and foamy kind of 3 foot
> chop yesterday . . . I noticed that I was not really having to brace
> very much for stability (at least consciously) despite the waves coming
> from various different directions. Stability seemed to increase the
> faster the boat went, at least when I wasnt slapping down the backsides
> of the waves.

> All this in a boat (Guillemot Coastal) that dumped me on the
> back side of a one foot wave within 45 seconds of first launch!

> So, my question for the lurking design gurus . . . does a kayak's
> forward movement add to its initial or final stability in any way?
> I assume most stability curves are based on a static model -- i.e.,
> assuming a boat lying still in the water. But does the movement of
> the kayak through the water create any kind of lift as the kayak begins
> to heel?

> Or is it just an illusion, based on the natural, subconscious
> bracing you get with each paddle stroke it takes to keep the boat
> moving in those kinds of conditions?

Messages In This Thread

Fluid stability?
Karl Coplan -- 7/3/1998, 12:04 am
Re: Fluid stability?
Mark Kanzler -- 7/4/1998, 9:58 am
Re: Fluid stability?
Paul Jacobson -- 7/4/1998, 12:56 pm
Re: Fluid stability?
Nick Schade -- 7/3/1998, 6:43 pm
Re: Fluid stability?
Rick C. -- 7/3/1998, 2:24 am
Re: Fluid stability?
Dave King -- 7/2/1998, 2:19 pm
Re: Fluid stability?
Tor-Henrik Furmyr -- 7/2/1998, 7:02 pm