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Re: Other: Practical differences in length
By:Toni V
Date: 10/13/2008, 3:53 am
In Response To: Re: Other: Practical differences in length (HenkA)

While a sphere - or half sphere for kayaks - has the least surface area, wave making will have quickly major effect. I once did series of Godzilla optimum hulls and they measure:

(I had beam limitation to 38cm (15inch) which is hit at 7 km/h (4,3 mph))
km/h__LWL,m__BWL,cm
4_____2.7_____51
6_____4.2_____40
8_____5.5_____38
11____6.6_____38

Same in funny units:
mph__LWL,ft__BWL,in
2.5____9.0_____20.2
3.7____13.6____15.9
5.0____18.2____15.0
4.3____21.6____15.0

So the semipherical shape is squished to long at quite low speeds. Of course these are not really viable kayak hulls to be paddled in waves and such but it'll give you some idea.

: No Paul, it is exactly the opposite. The body with the smallest surface area
: to volume ratio is the sphere. The more one deviates from that, the larger
: the relative surface area is. Thus, a longer kayak has more resistance
: despite the fact that the waterline is lower. The speed increase is a
: result of the larger hull speed despite the increased resistance.

: Henk

Messages In This Thread

Other: Practical differences in length
Kudzu -- 10/8/2008, 7:53 pm
Thanks, good info
Kudzu -- 10/11/2008, 12:33 pm
Re: Other: Practical differences in length
Bill Hamm -- 10/11/2008, 1:55 am
Re: Other: Practical differences in length *Pic*
Etienne Muller -- 10/10/2008, 3:28 pm
Re: Other: Practical differences in length
Carl Delo -- 10/16/2008, 1:03 am
Re: Other: Practical differences in length
Bill Hamm -- 10/16/2008, 2:18 pm
Re: Other: Practical differences in length
Bill Hamm -- 10/12/2008, 1:35 am
Re: Other: Practical differences in length
Ross Leidy -- 10/9/2008, 10:11 pm
And it's in your head too
Kudzu -- 10/11/2008, 12:32 pm
Re: Other: Practical differences in length
Scott Fitzgerrell -- 10/10/2008, 4:47 pm
Re: Other: Practical differences in length
Kudzu -- 10/9/2008, 10:22 pm
Re: Other: Practical differences in length
Bill Hamm -- 10/9/2008, 7:38 pm
Re: Other: Practical differences in length
Charlie -- 10/9/2008, 6:14 pm
Re: Other: Practical differences in length
Aaron H -- 10/10/2008, 10:52 am
Re: Other: Practical differences in length
Charlie -- 10/10/2008, 12:14 pm
Re: Other: Practical differences in length
Chris Sperry -- 10/9/2008, 10:55 pm
Re: Other: Practical differences in length
Aaron H -- 10/10/2008, 11:05 am
Re: Other: Practical differences in length
Chris Sperry -- 10/10/2008, 11:41 am
Re: Other: Practical differences in length *Pic*
Scott Fitzgerrell -- 10/10/2008, 4:43 pm
Re: Other: Practical differences in length
Chris Sperry -- 10/10/2008, 9:44 pm
Re: Other: Practical differences in length
Scott Fitzgerrell -- 10/11/2008, 4:55 pm
Re: Other: Practical differences in length
Aaron H -- 10/9/2008, 12:49 pm
Re: Other: Practical differences in length
Toni V -- 10/10/2008, 2:47 am
Re: Other: Practical differences in length
Aaron H -- 10/10/2008, 10:24 am
Re: Other: Practical differences in length
Bryan Hansel -- 10/10/2008, 1:17 am
Re: Other: Practical differences in length
Kudzu -- 10/9/2008, 12:59 pm
Re: Other: Practical differences in length
Don Lucas -- 10/9/2008, 10:13 am
Re: Other: Practical differences in length
Kudzu -- 10/9/2008, 10:33 am
Re: Other: Practical differences in length
Mike Savage -- 10/9/2008, 3:26 pm
Re: Other: Practical differences in length
Bryan Hansel -- 10/8/2008, 11:38 pm
Re: Other: Practical differences in length
Kudzu -- 10/8/2008, 11:59 pm
Re: Other: Practical differences in length
Bryan Hansel -- 10/10/2008, 9:01 am
Re: Other: Practical differences in length
Brian Nystrom -- 10/9/2008, 6:27 am
Re: Other: Practical differences in length
Toni V -- 10/9/2008, 1:59 am
Re: Other: Practical differences in length
Paul G. Jacobson -- 10/9/2008, 12:45 am
Re: Other: Practical differences in length
Paul G. Jacobson -- 10/8/2008, 10:46 pm
Re: Other: Practical differences in length
HenkA -- 10/12/2008, 3:03 am
Re: Other: Practical differences in length
Toni V -- 10/13/2008, 3:53 am
Re: Other: Practical differences in length
Bill Hamm -- 10/13/2008, 3:24 am
Re: Other: Practical differences in length
Bill Hamm -- 10/9/2008, 7:34 pm
Re: Other: Practical differences in length *Pic*
Clayton Plunkett -- 10/8/2008, 9:15 pm
Re: Other: Practical differences in length
Jerry -- 10/8/2008, 8:02 pm