The Kayak Forum is Sponsored By
|
|
|
| |
Kayak and Canoe Design Bulletin Board
Re: Suction and such...
Posted By: David Anderson In Response To: Re: Suction and such... (David Dick)
Date: Friday, 1 October 1999, at 1:17 p.m.
> Pete:
> Whatever the benefits of the bulb nose, big ships have an advantage in
> that the bulb stays at a (relatively) constant depth underway, the ships
> draft being relatively deep compared to wave height. I think we would lose
> much of the benefit as our bows are usually pitching up and down most of
> the time.> Has anyone seen one of these on the flat water racing canoes or kayaks?
> David
Good point--pitching is not a problem for small boats used on flat water. But, don't forget the other major problem with "bulbous bows"--hull speed. The purpose of the bulbous bow is to use the wave created by it to "cancel" the normal bow wave of the ship. As you know, the length of the bow wave is determined by the speed of the ship. This means that the distance the bulb extends ahead of the bow must be tuned for a certain ship speed for it to effectively cancel the bow wave. So, the bulbous bow only offers an advantage at a single speed--fine for long range ocean going ships, but not necessarily good for multi-speed use small craft. If the bulb isn't cancelling the bow wave, it's just more hull friction. So the challenge: Design an adjustable length bulbous bow.
| |
Kayak and Canoe Design Bulletin Board is maintained by Nick Schade - Guillemot Kayaks with WebBBS 5.12.
|
Boat Design |
|
|
|
