Re: [Paddlewise] Kayak speed vs length

From: Nick Schade <schade_at_guillemot-kayaks.com>
Date: Tue, 15 May 2001 09:01:16 -0400
Wetted surface area is determined solely by how much surface is wet. 
While there is a some relationship between how much weight the boat 
carries and wetted surface, it is not a direct correlation. Weight 
determines how much water is "displaced" and this is a volume. Some 
shapes enclose more volume with less surface area than others. The 
lowest wetted surface are for a given volume would be a hemisphere, 
in other words - a short, fat kayak. Long narrow shapes generally 
have more surface area for a given volume than short wide shapes. So 
longer boat will often have more wetted surface area than short ones.

At 4:10 PM -0400 5/14/01, KiAyker_at_aol.com wrote:
>In a message dated 5/14/2001 9:59:53 AM Eastern Daylight Time,
>schade_at_guillemot-kayaks.com writes:
>
>
>>  However shorter boats can have less drag at a given speed because
>>  most of the time the primary source of drag is the skin friction of
>>  water molecules moving against the hull of the boat. This drag is
>>  related to the wetted surface area of the boat. More wet surface,
>>  more drag. Shorter boats typically have less wetted surface and are
>>
>
>    I really do try to follow these discussions on boat and paddle physics,
>even though a lot of it is clearly over my head. I always though the wetted
>area of a boat was the result of the weight of the boat and how much water it
>displaced -- not the length. Is that not correct?
>
>Just wondering,
>
>Scott
>So.Cal.
>
>***************************************************************************
>PaddleWise Paddling Mailing List - Any opinions or suggestions expressed
>here are solely those of the writer(s). You must assume the entire
>responsibility for reliance upon them. All postings copyright the author.
>Submissions:     PaddleWise_at_PaddleWise.net
>Subscriptions:   PaddleWise-request_at_PaddleWise.net
>Website:         http://www.paddlewise.net/
>***************************************************************************

-- 
Nick Schade
Guillemot Kayaks
824 Thompson St
Glastonbury, CT 06033
(860) 659-8847

***************************************************************************
PaddleWise Paddling Mailing List - Any opinions or suggestions expressed
here are solely those of the writer(s). You must assume the entire
responsibility for reliance upon them. All postings copyright the author.
Submissions:     PaddleWise_at_PaddleWise.net
Subscriptions:   PaddleWise-request_at_PaddleWise.net
Website:         http://www.paddlewise.net/
***************************************************************************
Received on Tue May 15 2001 - 10:21:02 PDT

This archive was generated by hypermail 2.4.0 : Thu Aug 21 2025 - 16:30:42 PDT