End Plate Effect - Page 2 - SailNet Community

   Search Sailnet:

 forums  store  


Quick Menu
Forums           
Articles          
Galleries        
Boat Reviews  
Classifieds     
Search SailNet 
Boat Search (new)

Shop the
SailNet Store
Anchor Locker
Boatbuilding & Repair
Charts
Clothing
Electrical
Electronics
Engine
Hatches and Portlights
Interior And Galley
Maintenance
Marine Electronics
Navigation
Other Items
Plumbing and Pumps
Rigging
Safety
Sailing Hardware
Trailer & Watersports
Clearance Items

Advertise Here






Go Back   SailNet Community > General Interest > General Discussion (sailing related)
 Not a Member? 


Like Tree1Likes
Reply
 
LinkBack Thread Tools
  #11  
Old 02-26-2013
bobmcgov's Avatar
baDumbumbum
 
Join Date: Jul 2007
Location: Windy Wyoming
Posts: 1,022
Thanks: 0
Thanked 24 Times in 23 Posts
Rep Power: 8
bobmcgov will become famous soon enough
Re: End Plate Effect

Quote:
Originally Posted by obelisk View Post
Thanks for the great explanations. When I posted, I was thinking of end plate effect as pertaining to a keel, but lancelot brings up a good point about a loose footed main: Is the radius of the boom on an attached foot main enough to limit or eliminate the end plate effect?
In theory, a boom ought to act as an end plate & limit induced drag around the bottom of the sail. In practice, booms are nearly always taller than they are wide, to limit beam deflection. So they are not ideal shape for an endplate. You could build in a T-crosspiece for that purpose, but the added weight & windage might cancel any benefit. A bolt-roped foot + boom reduces air leakage; but it also limits draft (power) down low & harms sail shape. Some people believe a shelf foot is a good compromise, and the 'shelf' certainly extends laterally the end plate. But you almost need a flattening reef in any kind of wind.

And nothing you do at the sail's foot prevents induced drag at the top of the sail. & Pretty much the entire aft 60% of your sail is pulling the wrong way when close-hauled anyhow, so obsessing over air leakage around the foot overlooks larger realities. We're trying to use a lifting foil for forward thrust. The miracle is that it works at all!
__________________
Buccaneer18, Grainnia
SJ21, Diarmuid
Albin Ballad 30, Fionn
Reply With Quote Share with Facebook
  #12  
Old 02-26-2013
hellosailor's Avatar
Plausible Deniability
 
Join Date: Apr 2006
Posts: 10,415
Thanks: 1
Thanked 74 Times in 72 Posts
Rep Power: 10
hellosailor has a spectacular aura about hellosailor has a spectacular aura about
Re: End Plate Effect

You fill your pocket with nickels, and the weight of the nickels tears a hole in the bottom and the nickels start leaking out.

An end plate plugs the leak, so the nickels stay in your pocket. And the "fluid" (air or water) stays on the airfoil, instead of falling off the end.

You see them on aircraft wings these days too, they call them "winglets", the small vertical plate on the end of the wing. Same thing, keeps the nickels from rolling off.
Reply With Quote Share with Facebook
Reply


Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools

 
Posting Rules
You may post new threads
You may post replies
You may post attachments
You may edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On


Similar Threads
Thread Thread Starter Forum Replies Last Post
mast deck hinge plate and halyard organizer plate on spirit 23 Southron Spirit North American Yachts 4 03-31-2012 05:59 PM
Effect of the effect of the BP oil spill on Gulf Coast marine industry knothead Cruising & Liveaboard Forum 0 09-13-2010 07:23 PM
The Lee-Bow Effect Dan Dickison Learning to Sail Articles 0 10-27-2000 08:00 PM


All times are GMT -4. The time now is 03:46 AM.

Add to My Yahoo!         
Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
SEO by vBSEO 3.6.1
(c) Marine.com LLC 2000-2012