Custom Diffuser CFD (pic heavy)
 

Did some basic CFD fun with an FRS to test two different diffuser designs

*Results are not 100% accurate as the model(s) are semi-high poly, have been modeled with a complete covered belly pan and has a custom front bumper with ~30% more airflow (still pulled a .28 drag coefficient @100mph)

-The diffuser height/width difference, the more aggressive one is significantly more efficient at pulling air despite having a substantially lower attack angle
http://i.imgur.com/ltN9WFb.jpg

-Diffuser tunnel lengths and extraction area, the one on the left has almost twice the "airflow volume"
http://i.imgur.com/FRcuJDG.jpg

-This is the airflow of the more modest diffuser with pretty efficient vortex's at the rear of the car
http://i.imgur.com/CPdRyp0.png

-This is the airflow of the more aggressive diffuser, as you can see there is a substantial more blue (lower pressure air) being pulled from the rear thus its more efficient
http://i.imgur.com/egkxzhi.png

Nice! I love the ferrari diffusers, very cool work.

Same Id take the first one for sure

The first one would definitely reduce drag, but doesn't produce to much downforce due to its rake.... But boy is it pretty lol

Shut up dude. Make it, sell me it.

I'll take the one on the right if you do end up making one. Preferably single exit if you can and big enough to fit type 80 :)

Well.....that's one damn sexy diffuser.

Yeah I stylized the left one of off the 599/F-type diffuser (it did come out biblically sexy lol), while the right is model of off the 15' WRX Sti concept and is definitely more function >>> form.

Yeah i'm thinking of ideal mounting locations atm

Ideally I'd try to mount the diffuser on the 2 rear tow hooks & the attachment points on the lower control arms (where the drive way labs diffusers v1/v2 mounts at)... since one would have to cut the entire "fake diffuser" off the OEM bumper and the weight of the diffuser itself lol

Out of curiosity, which program are you using for modeling? My fiancée is about to finish her course work for a PhD in CFD. I'd be lying if I didn't think it was sexy that she could help design my custom car part ideas!


Sent from my iPhone using Tapatalk

For modeling, I use Trimble/Google Sketchup for the rough model, then go to a program like Maya or 3D Max for the HQ model (you can actually use those for 3d printing/custom fabbing). Shit I would kill for a woman who had a doctorate in CFD....... custom aero parts FTFW!!!

Take the new diffuser I concocted (replaces that kiddy diffuser on the right).. lol

http://i.imgur.com/JyHHyA0.jpg

By having the exhaust exit directly above actual diffuser exit, one can integrate the exhaust flow with the diffuser airflow allowing the airflow over the top of the diffuser to aid airflow extraction underneath the diffuser (essentially the exhaust gas "pulls" more air from the diffuser)

Granted one would have to remove the rear crash beam to get the exhaust in that set up... so this would really be track "only" diffuser or the for the "idgaf because racecar person" lol

Make it... I'll buy

Looks like a Challenge Stradale or Scuderia rear end with those tips and that diffuser

I like it!

Nick C.

Got the Ferrari part correct, it's based off the Ferrari 458 Speciale diffuser (minus the active aero)

If I'm not mistaken sw20kosh had a similar setup with a custom fabbed Lotus Elise Diffuser

Just some spin arounds I did of the race version, shows the airflow from multiple angles, pressure gradients etc..

*note the model is scaled WAY down so the while the airflow behavior & Drag Coefficient are accurate, the pressure reading aren't*

https://www.facebook.com/video.php?v...21&pnref=story