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

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 07-07-2021, 01:04 PM   #1 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 12,784
Thanks: 20,500
Thanked 6,307 Times in 3,907 Posts
Methods of Reducing Vehicle Aerodynamic Drag

I'll try for a link to this work by Upendar Rohatgi, at Brookhaven National Laboratory.
https://www.researchgate.net/publica...rodynamic_Drag
The particulars I was most interested in had to do with boat-tailing a full-size GM SUV.

__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/

Last edited by aerohead; 07-07-2021 at 01:06 PM.. Reason: add data
  Reply With Quote
The Following 2 Users Say Thank You to aerohead For This Useful Post:
AeroMcAeroFace (07-08-2021), Ecky (07-07-2021)
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 07-07-2021, 03:54 PM   #2 (permalink)
Master EcoModder
 
Ecky's Avatar
 
Join Date: Dec 2011
Location: Vermont
Posts: 4,416

Gaptooth (retired) - '00 Honda Insight
Team Honda
Gen-1 Insights
90 day: 54.26 mpg (US)

Such Fit - '07 Honda Fit Sport
90 day: 41.27 mpg (US)

Connect - '15 Ford Transit Connect XL
90 day: 21.26 mpg (US)

K-sight - '00 Honda K-sight
Team Honda
90 day: 46.5 mpg (US)

Aerocivic - '92 Honda Civic CX
90 day: 64.49 mpg (US)
Thanks: 2,251
Thanked 2,014 Times in 1,260 Posts
I'm also reading that he wasn't able to get any significant improvement (or change at all) with vortex generators.
  Reply With Quote
The Following User Says Thank You to Ecky For This Useful Post:
aerohead (07-07-2021)
Old 07-07-2021, 03:57 PM   #3 (permalink)
Master EcoModder
 
freebeard's Avatar
 
Join Date: Aug 2012
Location: northwest of normal
Posts: 19,692
Thanks: 5,524
Thanked 6,473 Times in 5,204 Posts
First mention of a perforated base plate I've seen in a while.

One quarter the benefit with one tenth the cost, weight and operational pain.
__________________
.
Conclussion: a realization that smacks you upside the head
_________________

"Anything is a smoke machine if you use it wrong enough" --AvE
_________________
  Reply With Quote
The Following User Says Thank You to freebeard For This Useful Post:
aerohead (07-07-2021)
Old 07-07-2021, 04:12 PM   #4 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 12,784
Thanks: 20,500
Thanked 6,307 Times in 3,907 Posts
VGs

When Gary Wheeler first went public with his Air Tabs VGs, it was within the context of providing for flow re-attachment onto the boot of a notchback car. He used his own Honda as an example.
Without some surface to re-attach to, I've no idea why anyone would have any expectation for improvement.
https://ecomodder.com/forum/member-a...s-air-tabs.jpg
Attached Thumbnails
Click image for larger version

Name:	member-aerohead-albums-articles+-+clippings-picture202-vortex-generators-air-tabs.jpg
Views:	28
Size:	38.4 KB
ID:	30991  
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
  Reply With Quote
Old 07-07-2021, 04:52 PM   #5 (permalink)
Master EcoModder
 
redneck's Avatar
 
Join Date: Jun 2009
Location: SC Lowcountry
Posts: 1,514

Geo XL1 - '94 Geo Metro
Team Metro
Boat tails and more mods
90 day: 72.22 mpg (US)

Big, Bad & Flat - '01 Dodge Ram 3500 SLT
Team Cummins
90 day: 21.13 mpg (US)
Thanks: 198
Thanked 1,212 Times in 604 Posts
.

Cheat sheet for the lazy...



CONCLUSSIONS


Quote:
1. Use of rear screen allows a reduction in aerodynamic drag of the vehicle model under consideration by up to ~6.5%. Efficiency of rear screens from point of view of drag reducing equally depends on configuration, dimensions and arrangement of screens as well as on model’s rear part configuration. The external mount of spare tire can be arranged to reduce drag.
Quote:
2. Rear fairing as part of flow separation area behind the vehicle can reduce aerodynamic drag of the vehicle with investigated configuration, by up to 26%. These results can be used at analysis of accuracy of calculation methods for defining aerodynamics of vehicles with separated areas. The results can also be useful for designers and design engineers in selection of vehicle external configuration.
Quote:
3. The other passive options also have potential to reduce drag. Front structural elements showed decrease in drag coefficient up to 2.24% and vortex generator showed a decrease up to 1.24%. There is scope to achieve additional improvement with the understanding of flow field and optimization of design.



>

.
__________________
Quote:
“The farther backward you can look, the farther forward you are likely to see.”

Winston Churchill.


Disclaimer...

I’m not a climatologist, aerodynamicist, virologist, physicist, astrodynamicist or marine biologist..

But...

I play one on the internet.

  Reply With Quote
The Following 2 Users Say Thank You to redneck For This Useful Post:
aerohead (07-07-2021), MeteorGray (07-14-2021)
Old 07-07-2021, 06:15 PM   #6 (permalink)
Master EcoModder
 
freebeard's Avatar
 
Join Date: Aug 2012
Location: northwest of normal
Posts: 19,692
Thanks: 5,524
Thanked 6,473 Times in 5,204 Posts
Quote:
CONCLUSSIONS
Is that like a realization that smacks you upside the head?
__________________
.
Conclussion: a realization that smacks you upside the head
_________________

"Anything is a smoke machine if you use it wrong enough" --AvE
_________________
  Reply With Quote
The Following User Says Thank You to freebeard For This Useful Post:
aerohead (07-07-2021)
Old 07-07-2021, 06:20 PM   #7 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 12,784
Thanks: 20,500
Thanked 6,307 Times in 3,907 Posts
conclussing the mind

That's exactly what I need!
If it takes a little shockwave to embedded, so be it.
__________________
Photobucket album: http://s1271.photobucket.com/albums/jj622/aerohead2/
  Reply With Quote
The Following 2 Users Say Thank You to aerohead For This Useful Post:
freebeard (07-07-2021), MeteorGray (07-14-2021)
Old 07-07-2021, 08:28 PM   #8 (permalink)
Master EcoModder
 
freebeard's Avatar
 
Join Date: Aug 2012
Location: northwest of normal
Posts: 19,692
Thanks: 5,524
Thanked 6,473 Times in 5,204 Posts
Woodie Guthrie has had his run in my signature.

redneck -- You want credit for that?
__________________
.
Conclussion: a realization that smacks you upside the head
_________________

"Anything is a smoke machine if you use it wrong enough" --AvE
_________________
  Reply With Quote
Old 07-07-2021, 10:48 PM   #9 (permalink)
Master EcoModder
 
redneck's Avatar
 
Join Date: Jun 2009
Location: SC Lowcountry
Posts: 1,514

Geo XL1 - '94 Geo Metro
Team Metro
Boat tails and more mods
90 day: 72.22 mpg (US)

Big, Bad & Flat - '01 Dodge Ram 3500 SLT
Team Cummins
90 day: 21.13 mpg (US)
Thanks: 198
Thanked 1,212 Times in 604 Posts
.

🤷

Not my job to proofread and correct published papers.

All I did was copy and paste.



(Screenshot)





🙃


>

.

__________________
Quote:
“The farther backward you can look, the farther forward you are likely to see.”

Winston Churchill.


Disclaimer...

I’m not a climatologist, aerodynamicist, virologist, physicist, astrodynamicist or marine biologist..

But...

I play one on the internet.

  Reply With Quote
The Following 4 Users Say Thank You to redneck For This Useful Post:
aerohead (07-09-2021), AeroMcAeroFace (07-08-2021), freebeard (07-08-2021), MeteorGray (07-14-2021)
Reply  Post New Thread


Thread Tools




Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com