Could a fan in front of a sailboat improve sailing? - Page 2 - SailNet Community
Reply
 
LinkBack Thread Tools
post #11 of 182 Old 07-21-2006
Junior Member
 
Join Date: Jul 2006
Location: Boston
Posts: 15
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Assuming you could find a place to mount this fan-tasy, you'd only ever be able to go as fast as the breeze coming off the fan. So, in the doldrums, you might gain something, but the bow would clearly be dipping. In a breeze, the fan would actually serve to slow down the wind coming at the boat. Want proof? Put a fan in a windward window at home. You'll get good airflow when it's still outside, but if the breeze picks up, you're better off with no fan at all.

In all, newbie though I be, I'll stick to "natural" windpower.
gabachojefe is offline  
Quote Quick Reply Share with Facebook
Sponsored Links
Advertisement
 
post #12 of 182 Old 07-21-2006 Thread Starter
Junior Member
 
Join Date: Jul 2006
Posts: 14
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Quote:
Originally Posted by gabachojefe
Assuming you could find a place to mount this fan-tasy, you'd only ever be able to go as fast as the breeze coming off the fan. So, in the doldrums, you might gain something, but the bow would clearly be dipping...

No, it is known by tacking into the wind the boat can have greater speed than the wind speed.


Bob
RGClark is offline  
Quote Quick Reply Share with Facebook
post #13 of 182 Old 07-21-2006
Junior Member
 
Join Date: Jul 2006
Location: Boston
Posts: 15
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
No argument here; meant that you'd have whatever speed you'd have in a similar breeze. I'll stand by my argument about interference, though: in anything more than a couple knots wind, you'd be doing yourself no favors.
gabachojefe is offline  
Quote Quick Reply Share with Facebook
post #14 of 182 Old 07-21-2006
Senior Member
 
Join Date: Aug 2002
Location: NC
Posts: 316
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Hey, SailorMitch...good to see you here again. How did the week sail with Denr go? Did you manage to get him sufficiently seasick?Kokopuff...
kokopelli9 is offline  
Quote Quick Reply Share with Facebook
post #15 of 182 Old 07-21-2006
Reward for lost Kraken!
 
hellosailor's Avatar
 
Join Date: Apr 2006
Posts: 11,492
Thanks: 5
Thanked 132 Times in 129 Posts
Rep Power: 11
   
If you'd mount a quantum attractor on the bow, you wouldn't need the sails or the fan.

Those things are so quaint, so 20th century! The good lord gave us eleven dimensions, why confine yourself to the first three or four of them?!
hellosailor is offline  
Quote Quick Reply Share with Facebook
post #16 of 182 Old 07-22-2006
Wish I never found SN!
 
SimonV's Avatar
 
Join Date: Jul 2006
Location: Brisbane Australia
Posts: 2,062
Thanks: 8
Thanked 4 Times in 4 Posts
Rep Power: 10
 
A fan of a size required to move air in the volume required to fill the sails would generate some large decibels. Think or the sound of a yachts wind generator in a BLOW, and that is being driven not driving air.............LEAVE CIVILZED SOCIOTY IF YOU MUST!!, GET A STINKY, NOISEY, POLLUTING, ENVIROMENTALY UNFREINDLY MOTOR DRIVEN MONSTROSITY.
SimonV is offline  
Quote Quick Reply Share with Facebook
post #17 of 182 Old 07-22-2006
Anthony C
 
Join Date: Jul 2006
Location: Seattle
Posts: 10
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
I have a better question... Can you lift yourself up by your bootstraps? What if you jump a little first to give yourself some momentum?

In all seriousness, the fan is going to act just like a propeller would in the water. It will give you some thrust if its big enough. You may even get a little extra from the sails, but no more than you would from equivalent thrust from a submerged propeller.

It's newton's third law of physics. Every action has an equal and opposite reaction. If there's thrust pushing the boat forward, its from the fan onto the sail and rig (pushing it equally backward). The fact that the boat moves forward because of the fan's thrust may draw a little extra air over the foil (sail) which will begin to cause some lift. But this isn't any different than if the 'fan' was underwater I would think.
anthonycolfelt is offline  
Quote Quick Reply Share with Facebook
post #18 of 182 Old 07-22-2006
Senior Member
 
pigslo's Avatar
 
Join Date: Nov 2004
Posts: 804
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 11
 
To all you guys that speculate "if the fan was big enough" and other such speculations...wrong. ANY wind produced from an object on the boat (even from the hot air of surfesq) is subject to an equal and opposite effect in the opposite direction. I believe that was one the first laws of physics.
Pigslo
pigslo is offline  
Quote Quick Reply Share with Facebook
post #19 of 182 Old 07-22-2006
Junior Member
 
Join Date: Jul 2006
Location: Boston
Posts: 15
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 0
 
Amazing the discussion even got this far. How about that quantum attractor?
gabachojefe is offline  
Quote Quick Reply Share with Facebook
post #20 of 182 Old 07-22-2006
Senior Moment
 
SailorMitch's Avatar
 
Join Date: Nov 2005
Location: MD
Posts: 1,931
Thanks: 0
Thanked 0 Times in 0 Posts
Rep Power: 10
 
Quote:
Originally Posted by RGClark
No, it is known by tacking into the wind the boat can have greater speed than the wind speed.


Bob
Bob,

Have you even tacked a sailboat?
SailorMitch is offline  
Quote Quick Reply Share with Facebook
Reply

Quick Reply
Message:
Options

By choosing to post the reply above you agree to the rules you agreed to when joining Sailnet.
Click Here to view those rules.

Register Now



In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.


User Name:
Password
Please enter a password for your user account. Note that passwords are case-sensitive.

Password:


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:
OR

Log-in









Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.




Currently Active Users Viewing This Thread: 1 (0 members and 1 guests)
 
Thread Tools
Show Printable Version Show Printable Version
Email this Page Email this Page



Similar Threads
Thread Thread Starter Forum Replies Last Post
sailing for the disabled amangos General Discussion (sailing related) 0 06-19-2006 01:30 AM
ISAF Eligibility Requirements paulk Racing 4 02-05-2001 11:25 AM

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are On

 
For the best viewing experience please update your browser to Google Chrome