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Re: Placebo effect-why?
By:Gennie
Date: 12/22/2004, 2:37 am
In Response To: Re: Placebo effect-why? (Brian Nystrom)

: One other consideration is that polishing is not necessarily beneficial,
: either. It's common among sail racers to sand the surface of their hulls
: lightly (IIRC 400 grit creates the preferred texture), which reduces drag
: in the water. Note that this produces a uniform surface and is not the
: same as having a scratched hull or varnish with lumps, runs and brush
: streaks. Whether this applies to kayaks and their lower speeds is
: debatable and I don't claim to know the answer. AFAIK, no one has done a
: definitive study on this.

A freind of my sisters races sailboats told me that a while back. The end goal was to drag along a thin coat of water, because water/water resistance should be very low. My guess is that the required roughness of the surface is dependable of the sailing speed, but that is pure guessing!
I know that glider-aeroplanes has a wire (or something) on the wing at a distance from the leading edge of the wing to create a controlled turbulence. The goal is NOT to avoid turbulence (probably impossible) but to control it. It has been 14 years since I dropped out of ingeneering school, but I think hydrodynamics and aerodymnamics are a lot alike.

Gennie
www.byg-kajak.dk

Messages In This Thread

Strip: Cloth weight opinions
Holmes -- 12/17/2004, 12:33 am
Re: Strip: Cloth weight opinions
Jim Looker -- 12/20/2004, 10:49 am
Re: Strip: Cloth weight opinions
J. R. Ackley -- 12/21/2004, 7:55 pm
Re: Strip: Cloth weight opinions
pikabike -- 12/17/2004, 12:58 pm
Re: Strip: Cloth weight opinions
Paul Jacob -- 12/17/2004, 12:53 pm
Re: Strip: Cloth weight opinions
Rob Macks -- 12/17/2004, 1:51 pm
Re: Strip: Cloth weight opinions
Paul Jacob -- 12/17/2004, 6:56 pm
Re: Strip: Cloth weight opinions
Mike Scarborough -- 12/17/2004, 9:18 am
Re: Strip: Cloth weight opinions
bryan gorr -- 12/17/2004, 2:53 am
Re: Strip: Cloth weight opinions
Thomas Duncan -- 12/17/2004, 8:00 am
Graphite Experience
Jay Doorly -- 12/18/2004, 1:59 am
Re: You are waxing poetic.
Gordon Niessen -- 12/20/2004, 7:26 am
Tungsten filled epoxy.
John Monroe -- 12/20/2004, 4:04 am
Re: Tungsten filled epoxy.
Robert N Pruden -- 12/20/2004, 12:42 pm
Re: Carbide filled epoxy. Blue *LINK*
John Monroe -- 12/21/2004, 4:08 am
in a candy store
LeeG -- 12/20/2004, 6:27 pm
Placebo effect
Brian Nystrom -- 12/19/2004, 8:44 am
Re: Placebo effect
Jay Doorly -- 12/20/2004, 11:41 pm
Re: Placebo effect-why?
Thomas Duncan -- 12/19/2004, 7:46 pm
Re: Placebo effect-why?
John D. -- 12/20/2004, 12:48 am
Re: Placebo effect-why?
Jay Doorly -- 12/21/2004, 12:40 am
Re: Placebo effect-why?
Rory -- 12/21/2004, 4:37 am
Re: Placebo effect-why?
John D. -- 12/21/2004, 2:11 am
Re: Placebo effect-why?
Brian Nystrom -- 12/21/2004, 12:27 pm
Re: Placebo effect-why?
Gennie -- 12/22/2004, 2:37 am
Re: Placebo effect-why?
Chuck in Pa -- 12/21/2004, 10:24 pm
Re: Placebo effect-why?
Jay Doorly -- 12/21/2004, 11:22 pm
Re: Graphite Experience
Thomas Duncan -- 12/18/2004, 10:38 am
Re: Graphite Experience
LeeG -- 12/18/2004, 9:26 am
thought experiment
LeeG -- 12/17/2004, 8:14 am
Re: thought experiment
Thomas Duncan -- 12/17/2004, 9:25 am
Re: Real experiment
pikabike -- 12/17/2004, 1:10 pm
Re: Real experiment
LeeG -- 12/18/2004, 9:10 am
Re: thought experiment *LINK*
Glen Smith -- 12/17/2004, 11:16 am