Thread: Air Curtain
View Single Post
Old 02-24-2016, 10:18 PM   #101 (permalink)
Vman455
Moderator
 
Vman455's Avatar
 
Join Date: Feb 2012
Location: Urbana, IL
Posts: 1,939

Pope Pious the Prius - '13 Toyota Prius Two
Team Toyota
SUV
90 day: 51.62 mpg (US)

Tycho the Truck - '91 Toyota Pickup DLX 4WD
90 day: 22.22 mpg (US)
Thanks: 199
Thanked 1,806 Times in 942 Posts
Quote:
Originally Posted by mcrews View Post
THIS!
"Back in the day", front ducts were for cooling the brakes.
Not just back in the day. The current Viper has inlets at the outer edge of the bumper for air curtains:



...along with black ducts at the lower corners of the grill for brake cooling:



Quote:
Originally Posted by hat_man View Post
Not that I would even know how to implement something like this, but I do like to learn as much as I can. After reading the last 10 pages it seems like these air curtains work by moving air from the higher pressure area in from of the vehicle (bumper area) through slots, and increasing it's velocity by narrowing the slots into slits before expelling the air across the face of the front wheels. This in turn either helps fill the cavity of the front wheel well causing a "boundary" so that the air moving around the vehicle doesn't get "scrambled" causing drag? Or the air coming through the slits is of a greater velocity (pressure?) than the air moving around the corner (bumper) creating this "curtain", again keeping the attached air from getting "scrambled"?

I am assuming these slits have their opening in the wheel well somewhere near the vertical mid-line of the tire or are they closer to the outer edge of the tire?

I know the "particulars" of this are way above my head, but man I do love to learn.
I looked at the various BMW air curtain ducts up close at the Chicago Auto Show last week, especially on the i8. They're several inches long, roughly in the middle of the wheel opening, and very close to the outside edge of the wheel well. Also, the angle of the ducting looks to be critical--if the jet shoots too far to the inside, it will simply hit the tire, and if too far to the outside, it will disrupt airflow coming off the bumper. I doubt anyone here could get these to work without a wind tunnel.

__________________
UIUC Aerospace Engineering
www.amateuraerodynamics.com
  Reply With Quote
The Following User Says Thank You to Vman455 For This Useful Post:
aerohead (02-25-2016)