View Single Post
Old 07-22-2018, 01:52 AM   #8 (permalink)
Master EcoModder
freebeard's Avatar
Join Date: Aug 2012
Location: northwest of normal
Posts: 14,326
Thanks: 3,541
Thanked 4,736 Times in 3,770 Posts
Air brakes are perpendicular [in use]. The perforations increase turbulence over a solid plate, thus increasing drag.

For the parallel case, I saw a PDF (that DDG can't find today) on using round holes on the front of the sides of cattle trucks, over horizontal rectangular slot the length of the sides (as is the fashion) to prevent animals suffocating. So location and shape/size matter.
God's blessing on this wonderful world!
  Reply With Quote
The Following User Says Thank You to freebeard For This Useful Post:
aerohead (07-25-2018)