Boat Design Forums  |  Boat Design Directory  |  Boat Design Gallery  |  Boat Design Wiki (beta)  |  Boat Design Book Store  |  Thanks to Our Site Sponsors  |  Sitemap

Go Back   Boat Design Forums > Design > Sailboats
Register FAQ Members List Calendar Search Today's Posts Mark Forums Read

Reply
 
Thread Tools Search this Thread Display Modes
  #31  
Old 07-17-2009, 07:04 AM
Doug Lord's Avatar
Doug Lord Doug Lord is online now
Senior Member
 
Join Date: May 2009
Rep: 72 Posts: 414
Location: Cocoa Beach, Florida
Quote:
Originally Posted by Munter View Post
Doug at less than 20kts you might not use the power foil - how do you balance the boat during this time? Through sheeting and weight adjustment like a moth?
========================
Yes-probably using sliding bench seats...you may be able to see them on this model:
Attached Thumbnails
power-foils-added-power-carry-sail-aero-20model.jpg  
Attached Images
 
__________________
yes, it is a revolution
--------------
--the Gallery is open(new pictures)
Reply With Quote
  #32  
Old 07-18-2009, 05:57 AM
Richard Atkin Richard Atkin is offline
atn_atkin@hotmail.com
 
Join Date: Jul 2007
Rep: 180 Posts: 568
Location: Wellington, New Zealand
I like it
Reply With Quote
  #33  
Old 07-18-2009, 06:41 AM
Doug Lord's Avatar
Doug Lord Doug Lord is online now
Senior Member
 
Join Date: May 2009
Rep: 72 Posts: 414
Location: Cocoa Beach, Florida
Thanks,Richard.
__________________
yes, it is a revolution
--------------
--the Gallery is open(new pictures)
Reply With Quote
  #34  
Old 08-18-2009, 10:35 PM
Doug Lord's Avatar
Doug Lord Doug Lord is online now
Senior Member
 
Join Date: May 2009
Rep: 72 Posts: 414
Location: Cocoa Beach, Florida
Power Foils

Power Foils on monohull foilers will work very similarly to the way the windward foil on the Hobie Trifoiler and the Rave work-but the main difference is that they will only be used in heavier wind- with the boat sailing on just two foils in light and moderate wind.This is what Greg Ketterman had to say about using a windward foil to develop negative lift:

"Hydrofoil boats can be categorized into two categories; 1) Incidence controlled hydrofoils and 2) surface piercing hydrofoils. The difference lies in the way the boat maintains the proper altitude above the water surface. A surface piercing hydrofoil boat maintains proper height by varying the amount of foil submerged. The boat raises up as the speed increases and reduces the amount of foil submerged and therefore the lift. The boat finds equilibrium at the proper altitude. An incidence controlled hydrofoil sailboat has a mechanism that controls the angle of attack of the foil to maintain the proper altitude. It is generally believed that surface piercing is simpler, but incidence control is more efficient. In reality, it is the method that works with fewer problems that is simpler.
From the beginning it was felt that incidence control was better suited for a sailboat even though most of the existing hydrofoil sailboats were of the surface piercing type. There are many advantages of the incidence controlled foils; however, the most important is what I call the DLA (dynamic leveling affect). This is the increase in righting moment or stability due to the ability of the windward foil to pull down. The DLA has little affect on the low wind performance, but it essentially makes the top speed of the boat limited to the strength of the boat. Conventional boats with a finite amount of righting moment can only extract so much power from the wind, but with the DLA, the righting moment is virtually unlimited."
http://www.hobiecat.com/sailing/TriF...lls%201990.htm
__________________
yes, it is a revolution
--------------
--the Gallery is open(new pictures)
Reply With Quote
Reply



Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes


Similar Threads
Thread Thread Starter Forum Replies Last Post
SAIL vs POWER brian eiland Boat Design 29 10-10-2007 07:05 PM
What's better Sail Or Power Adz Sailboats 34 09-12-2005 09:50 AM
Sail power and horse power? kjell Motorsailers 12 09-03-2005 04:20 AM
Why sail over power? Why power over sail? mackid068 Boat Design 19 04-12-2005 08:54 AM
SAIL to POWER tschienque Propulsion 4 12-23-2004 12:45 PM


All times are GMT -5. The time now is 06:46 PM.


Powered by: vBulletin 3 Copyright ©2000 - 2009, Jelsoft Enterprises Ltd.
Web Site Design and Content Copyright ©1999 - 2009 Boat Design Net