View Single Post
Old 05-13-2018, 09:22 AM   #23 (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 1,805 Times in 941 Posts
Quote:
Originally Posted by freebeard View Post
If you boat tail from inside to inside of the tail lights it saves a lot of fiddling with wiring & etc., but it induces separation before the boat tail. So — put [chevron-shaped] wickerbills or Gurney flaps at the leading edge of the taillights to wrap the airflow around.
After driving through a snowstorm in Pennsylvania, the salt spray patterns on my tail were illustrative of where there was attached airflow and where separation; the cut-outs near the lights were covered in salt, but two-thirds of the way back were clean, indicating flow reattachment.

You'll be giving up some energy in forming that recirculating vortex behind the taillights, but not enough that I'd bother with vortex traps.

__________________
UIUC Aerospace Engineering
www.amateuraerodynamics.com
  Reply With Quote
The Following User Says Thank You to Vman455 For This Useful Post:
aerohead (05-14-2018)