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Re: integral rudder...again
By:Mark Kanzler
Date: 8/29/1998, 10:55 am
In Response To: Re: integral rudder...again (Nolan Penney)

I'd have to disagree. As the aspect ratio gets lower and lower, the wing behaves less like an airfoil. Airfoil, by (aerodynamicists) definition is infinitely long (infinite span), and is therefore only subject to 2D flow. A wing is not an airfoil, and vice versa. In wind tunnels, the airfoil usually spans the tunnel and attaches at the walls. This is stil imperfect because where the wing joins the wall there is some interference, but data is taken at midspan when airfoil data is desired. When wing data is desired, the data is taken in "strips" along the span (sort of a checkerboard pattern of pressure ports and/or tufts)

The aspect ratio of a kayak (span / chord) is about .05, where on an airplane it's around 10 nominally. The flow around a kayak does not go from bow to stern directly, it flow upward as well.

This is not to sat that there are no airfoil effects, only that there are many other flow effects that make predicting hoe thw shape as viewed from above will effect the outcome, and corollation to airfoil data is certainly not the way to go.

A kayak is shaped more like a wingtip than like a section cut out of a wing. Because of this and its shortness in the spanwise direction (beam), I would not expect it to behave in a simple manner.

I really enjoyed the golfball article, Bill Nye is one of my all time heros. He brings science to kids in a way that is fun and understandable. When I was a kid, I was wierd because I really enjoyed science classes. I enjoyed doing experiments at home, especially where boats, airplanes, or pyrotechnics were involved.

Messages In This Thread

integral rudder...again
Tom Scheibe -- 8/24/1998, 7:03 pm
Re: integral rudder... another question
Edgar Kleindinst -- 8/30/1998, 12:01 am
Re: integral rudder... another question
Nick Schade -- 8/31/1998, 5:51 pm
Re: integral rudder... another question
Edgar Kleindinst -- 9/4/1998, 5:29 pm
Re: integral rudder... another question
Tom Scheibe -- 8/31/1998, 2:18 pm
Re: integral rudder... another question
Joe Greenley -- 8/29/1998, 2:21 pm
Re: integral rudder... Dagger Atlantis
Mark Kanzler -- 8/31/1998, 12:07 am
Re: integral rudder on Dagger Sitka
Ross Leidy -- 9/1/1998, 1:54 pm
Please describe control cables
Pete Ford -- 8/25/1998, 7:47 pm
Re: Please describe control cables
Tom Scheibe -- 8/25/1998, 11:23 pm
Re: Please describe control cables
Mark Bodnar -- 8/26/1998, 6:03 pm
Re: Please describe control cables
Tom Scheibe -- 8/27/1998, 4:29 pm
Re: Please describe control cables
Mark Kanzler -- 8/27/1998, 6:55 pm
Re: Please describe control cables
Nolan Penney -- 8/28/1998, 6:49 am
Re: integral rudder...again
Nolan -- 8/25/1998, 6:46 am
Re: integral rudder...again
Tom Scheibe -- 8/25/1998, 4:36 pm
Re: integral rudder...again
Tom Scheibe -- 8/25/1998, 5:11 pm
Re: integral rudder...again
Nolan Penney -- 8/26/1998, 6:31 am
Re: integral rudder...again
Tom Scheibe -- 8/26/1998, 2:30 pm
Re: integral rudder...again
Nolan Penney -- 8/26/1998, 3:06 pm
Re: integral rudder...again
Mark Kanzler -- 8/28/1998, 12:07 am
Re: integral rudder...again
Nolan Penney -- 8/27/1998, 3:19 pm
Re: integral rudder...again
Mark Kanzler -- 8/27/1998, 7:09 pm
Re: integral rudder...again
Nolan Penney -- 8/28/1998, 7:05 am
Re: integral rudder...again
Mark Kanzler -- 8/28/1998, 11:08 am
Re: integral rudder...again
Nolan Penney -- 8/28/1998, 3:14 pm
Re: integral rudder...again
Mark Kanzler -- 8/29/1998, 10:55 am
Re: integral rudder...again
Mark Kanzler -- 8/28/1998, 10:59 am
Re: integral rudder...again
Nolan Penney -- 8/28/1998, 3:24 pm
Re: integral rudder...again
Mark Kanzler -- 8/29/1998, 11:10 am
Re: integral rudder...again
chris_rolt -- 8/28/1998, 7:14 pm
Re: integral rudder...again
Mark Kanzler -- 8/29/1998, 11:34 am
Re: integral rudder...again
Mark Kanzler -- 8/28/1998, 11:49 am
Re: New BBS Format
Mark Kanzler -- 8/27/1998, 7:14 pm
Re: integral rudder...again
Mark Kanzler -- 8/25/1998, 4:49 pm
A Picture - Rudder on a Cobra Kayak
Tom W. -- 8/25/1998, 3:19 pm
Re: A Picture - Rudder on a Cobra Kayak
Mark Kanzler -- 8/25/1998, 3:55 pm
Re: integral rudder...again
John Lange -- 8/25/1998, 1:01 pm
Re: Dagger Sitka Link
Mark Kanzler -- 8/25/1998, 3:52 pm
Re: Dagger Sitka Link
John Lange -- 8/25/1998, 4:25 pm
Re: Dagger Sitka Link
Mark Kanzler -- 8/25/1998, 4:37 pm
Re: 24' x 26"??
Wynne -- 8/27/1998, 3:04 pm
Re: 24' x 26"??
Mark Kanzler -- 8/27/1998, 7:21 pm
Re: integral rudder...again
Mark Kanzler -- 8/25/1998, 10:55 am
Re: Flow tank testing.
Mark Kanzler -- 8/24/1998, 8:37 pm