Go Back   EcoModder Forum > EcoModding > Aerodynamics
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 09-17-2009, 11:58 AM   #1 (permalink)
Master EcoModder
 
Join Date: Feb 2008
Location: belgium
Posts: 663

vectra a - '95 Opel Vectra GLS
90 day: 37.51 mpg (US)
Thanks: 14
Thanked 61 Times in 44 Posts
rounded aft wheel well edge?

after comparing some CFG images found online, it would appear as though generally there's quite a lot of air exiting the front wheelwell on the underbody, this makes sence as the wheel leaves a low pressure areas wich sucks the air our, wich gets trapped in the wheelwell... this doesn't look like a very desirable situation, and a lot of small dam designs in front of the wheelhell seems to sugest keeping air out of the well is quite important... however likely quite a portion of this air might get in there trough the grill.

now to get to my question, would it be a good idea to round the transition of the wheelwell to the underbody? perhaps by adding a quart section of a plastic pipe, or some flexible material that's curved backwards?

in theory you'd want to make an exit duct i guess like some racecars, but since it's not practical to hack up your car for most of us perhaps there's some gains to be squeezed out of this with a fairly simple mod.

also perhaps small vanes behind the tire and wheellwell could straighten out this flow and reduce drag even further?

__________________
aer·o·dy·nam·ics: the science of passing gass

*i can coast for miles and miles and miles*
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 09-17-2009, 12:18 PM   #2 (permalink)
Hypermiler
 
PaleMelanesian's Avatar
 
Join Date: Dec 2007
Location: Texas
Posts: 2,321

PaleCivic (retired) - '96 Honda Civic DX Sedan
90 day: 69.2 mpg (US)

PaleFit - '09 Honda Fit Sport
Team Honda
Wagons
90 day: 44.06 mpg (US)
Thanks: 611
Thanked 433 Times in 283 Posts
Not quite what you're talking about, but similar. The rear edge of the front wheel well is curved in for smoother airflow.
__________________



11-mile commute: 100 mpg - - - Tank: 90.2 mpg / 1191 miles
  Reply With Quote
Old 09-17-2009, 12:18 PM   #3 (permalink)
EcoModder
 
Join Date: Jul 2008
Location: North Central Alabama
Posts: 572

Big Salsa - '04 Toyota Sienna LE

Silver - '10 Toyota Prius III
Thanks: 110
Thanked 123 Times in 71 Posts
Kind of like the first generation Insight did along the side of the car, a nice rounding. I had not thought about it to the bottom, but it may help. As far as the veins go, there are some general rules that should be followed to transition turbulent flow back to laminar. If I remember correctly (this is a big if), you need a tube (or grate) that is AT LEAST twice as long as it is in diameter. We had a setup we used that would create turbulent flow in one section, but before getting to the next we had to have good laminar flow again, so we used straws bundled together. I don't know if the same rule applies to spacing between vanes, or if it works on a larger scale than straw-diameter tubes (which would not be practical for cars with road grime).
__________________
  Reply With Quote
Old 09-17-2009, 01:17 PM   #4 (permalink)
Master EcoModder
 
Join Date: Feb 2008
Location: belgium
Posts: 663

vectra a - '95 Opel Vectra GLS
90 day: 37.51 mpg (US)
Thanks: 14
Thanked 61 Times in 44 Posts
Quote:
Not quite what you're talking about, but similar. The rear edge of the front wheel well is curved in for smoother airflow.
something like that at the bottom

the shape of the insight should be on every car as the upper rear "corner" of a wheelwell seems to be the place where a lot of air exits, unfortunately traditionally the shape is more scoop like then exit like.... fender vents and something like the insight might be a good thing

this image i googled up shows both airstreams....


both seem to be fed by the font grill... this might explain in part why a front grill block is so effective... it will reduce these turbulent streams wich will also effect the rest of the wake i think
__________________
aer·o·dy·nam·ics: the science of passing gass

*i can coast for miles and miles and miles*
  Reply With Quote
Old 09-17-2009, 06:10 PM   #5 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 15,892
Thanks: 23,969
Thanked 7,221 Times in 4,648 Posts
rounded

Remember,the forward stagnation pressure is communicated through the cooling system,and as soon as the air passes the heat exchangers it's going to "look" for a way out.That speeding low pressure air along the side of the car is the first candidate if the under hood air can get to it.------- You can design for that like Kamm and Morelli,or you can move the entire cooling system to the rear like Ford did with the Probe series concepts.
  Reply With Quote
Old 09-17-2009, 11:37 PM   #6 (permalink)
Master EcoModder
 
Join Date: Jan 2009
Location: Maui, Hawaii
Posts: 813
Thanks: 5
Thanked 34 Times in 26 Posts
The NA Miata has angled inward and radiused panels behind the front wheels


  Reply With Quote
Old 09-19-2009, 05:52 PM   #7 (permalink)
EcoModding Lurker
 
anthonye81's Avatar
 
Join Date: Feb 2009
Location: Leicester, UK
Posts: 21

Boxer - '95 Alfa Romeo 146 1.7ie
90 day: 28.98 mpg (US)
Thanks: 3
Thanked 1 Time in 1 Post
Quote:
Originally Posted by winkosmosis View Post
The NA Miata has angled inward and radiused panels behind the front wheels
The wheel arches look angled inward at both the leading and trailing edges around all the wheels. Isn't that just a body style thing?
__________________
Anthony
  Reply With Quote
Old 09-20-2009, 01:59 PM   #8 (permalink)
Master EcoModder
 
Join Date: Feb 2008
Location: belgium
Posts: 663

vectra a - '95 Opel Vectra GLS
90 day: 37.51 mpg (US)
Thanks: 14
Thanked 61 Times in 44 Posts
first gen miatas (with the pop up headlights) apperently had the insight style wheel wells

laters models seemed to have a more conventional flattened edge.
__________________
aer·o·dy·nam·ics: the science of passing gass

*i can coast for miles and miles and miles*
  Reply With Quote
Old 09-20-2009, 08:50 PM   #9 (permalink)
Master EcoModder
 
Join Date: Jan 2009
Location: Maui, Hawaii
Posts: 813
Thanks: 5
Thanked 34 Times in 26 Posts
Quote:
Originally Posted by anthonye81 View Post
The wheel arches look angled inward at both the leading and trailing edges around all the wheels. Isn't that just a body style thing?
lunarhighway's pic shows it better. Only the rear edge of the front wheelwells

  Reply With Quote
Reply  Post New Thread




Similar Threads
Thread Thread Starter Forum Replies Last Post
Louvered wheel wells on race cars Tango Charlie Aerodynamics 46 03-10-2018 03:57 PM
DIY: plastic rear wheel skirts (Geo Metro) MetroMPG DIY / How-to 57 06-12-2014 09:16 AM
Front Wheel Skirts; 1950 Nash Ambassador Rokeby Aerodynamics 18 04-06-2014 12:14 PM
Help with my aero mods: 1.8L 05 Auto Toyota Corolla blackjackel Aerodynamics 73 11-22-2011 09:55 PM
Rear wheel skirt / cover question pasadena_commut Aerodynamics 5 02-16-2009 04:50 AM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2024, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com