View Single Post
Old 01-23-2014, 06:27 PM   #29 (permalink)
aerohead
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 16,333
Thanks: 24,453
Thanked 7,394 Times in 4,789 Posts
steep

Quote:
Originally Posted by KamperBob View Post
If the bottom rear slope of old bugs where air vents are located are too steep to support attached flow then I wonder why. It occurs to me that suction effect from flow detachment could aid in cooling an air-cooled rear engine. Tufts tied to vent slots should confirm flow direction at speed...
Hucho says that the longitudinal vortices of the Bug's pseudo-Jaray roofline will help induce a high deflection attached flow downwash at the center of the back.This would aid cooling,although the high drag vortices would raise the road load,requiring more power (heat flux) which would have to be dealt with.
In 1936 or so,the Beetle's Cd 0.495 would have been considered quite low compared to contemporary cars.
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
  Reply With Quote