View Single Post
Old 11-17-2005, 08:53 AM   #4
brian eiland
Senior Member
 
brian eiland's Avatar
 
Join Date: Jul 2004
Location: Washington DC, Annapolis MD, Thailand
Posts: 634
Ducted vs Peripheral Drive

Quote:
Originally Posted by Codger
Peripheral Drives are called Ducted Fans when they are moving air instead of water. Substantial increases in efficiency in air. Flew a small aircraft once with that configuration, worked very well. Wonder if the same holds true in water. Any hydrodynamicists hanging around here?
Kort nozzels are ducted marine propellers. These are very good for maximizing thrust of the enclosed prop on tugs, etc, but suffer from higher drag at higher boat speeds.

Note that the peripheral drive is significantly different than a ducted fan(prop) unit in that the blades are attached at the perimeter wall rather than just 'in close proximity'.
brian eiland is offline   Reply With Quote