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

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 03-22-2009, 04:57 AM   #1 (permalink)
EcoModding Apprentice
 
Join Date: Sep 2008
Location: Upstate NY
Posts: 190

GreenMile - '00 Mazda Protege ES
90 day: 34.45 mpg (US)
Thanks: 0
Thanked 5 Times in 3 Posts
Toying with some other model designs...

This design actually isn't based on the Aptera, but it looks damn close for the main body. They look similar for the same reasons that the Prius and Insight do.

Couple days ago I was toying with trying to make the roof line drop low to make a small suction area in the rear, as opposed to a normal car. I found that in order to get an acceptable slope the vehicle had to be very long to give the passengers enough head room.

Then it hit me (and I realized immediately when I did it that it made the side profile exactly like the Aptera) that by raising the rear up by just tilting the model allows for that head space. I'm guessing that is why Aptera does it too, but obviously can't say for sure.

Anyways here we are:





The photo doesn't show it, but there are two seats side by side there. As far as scale, it is about the same length and width as a Mazda Protege.

The next version will hopefully have full wheel enclosures.

Attached Thumbnails
Click image for larger version

Name:	IsoView.jpg
Views:	137
Size:	102.5 KB
ID:	3009   Click image for larger version

Name:	SideView.jpg
Views:	139
Size:	51.8 KB
ID:	3010  
__________________
http://benw385.vox.com/
'Blog' on the open source electric motorcycle project.

Please come visit and comment!
  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 03-22-2009, 06:51 AM   #2 (permalink)
Master EcoModder
 
NeilBlanchard's Avatar
 
Join Date: May 2008
Location: Maynard, MA Eaarth
Posts: 7,901

Mica Blue - '05 Scion xA RS 2.0
Team Toyota
90 day: 42.48 mpg (US)

Forest - '15 Nissan Leaf S
Team Nissan
90 day: 156.46 mpg (US)

Number 7 - '15 VW e-Golf SEL
TEAM VW AUDI Group
90 day: 155.81 mpg (US)
Thanks: 3,466
Thanked 2,934 Times in 1,837 Posts
Hi,

Have you looked at the Schlor Pillbug? It seated 5 or 6 people and had a Cd of just 0.13 -- better than the current Aptera.
__________________
Sincerely, Neil

http://neilblanchard.blogspot.com/
  Reply With Quote
Old 03-22-2009, 12:12 PM   #3 (permalink)
EcoModding Apprentice
 
Join Date: Sep 2008
Location: Upstate NY
Posts: 190

GreenMile - '00 Mazda Protege ES
90 day: 34.45 mpg (US)
Thanks: 0
Thanked 5 Times in 3 Posts
Ya I have seen those before. The vehicle is too large for what I would want to build and would cost too much. My vehicle would still have a lower CdA even if it had a higher Cd (unless of course my Cd was quite a bit higher).

Trying to balance weight and CdA against their spiraling cost effects on materials, the drivetrain etc.
__________________
http://benw385.vox.com/
'Blog' on the open source electric motorcycle project.

Please come visit and comment!
  Reply With Quote
Old 03-22-2009, 07:50 PM   #4 (permalink)
EcoModding Apprentice
 
Join Date: Sep 2008
Location: Upstate NY
Posts: 190

GreenMile - '00 Mazda Protege ES
90 day: 34.45 mpg (US)
Thanks: 0
Thanked 5 Times in 3 Posts
Finally figured out a good way to model the rear wheel enclosure, it's pretty close to the way I would want the final version. I also thought the Carbon Fiber looked kinda crappy, so it's switched to a brushed aluminum look for now.



Attached Thumbnails
Click image for larger version

Name:	IsoView.jpg
Views:	108
Size:	54.3 KB
ID:	3014   Click image for larger version

Name:	RearWheelEnclosure.jpg
Views:	112
Size:	53.5 KB
ID:	3015  
__________________
http://benw385.vox.com/
'Blog' on the open source electric motorcycle project.

Please come visit and comment!
  Reply With Quote
Old 03-23-2009, 02:00 PM   #5 (permalink)
EcoModding Apprentice
 
Bicycle Bob's Avatar
 
Join Date: May 2008
Location: N. Saskatchewan, CA
Posts: 1,728

Appliance White - '93 Geo Metro 4-Dr. Auto
Last 3: 42.35 mpg (US)

Stealth RV - '91 Chevy Sprint Base
Thanks: 89
Thanked 424 Times in 298 Posts
Raising the back to gain headroom is fine, but we can't slope the belly pan as much as the roof, because the air supply to that area is more limited, making separation more likely.
  Reply With Quote
Old 03-23-2009, 04:32 PM   #6 (permalink)
EcoModding Apprentice
 
Join Date: Sep 2008
Location: Upstate NY
Posts: 190

GreenMile - '00 Mazda Protege ES
90 day: 34.45 mpg (US)
Thanks: 0
Thanked 5 Times in 3 Posts
Top angle is about 12 degrees bottom is about 10.5; so ya the angles are pretty close. But the Rear wheel fills in much of that space (perhaps more I may stretch the wheel faring farther forward) and the the shape is fully tear dropping in 3d, so air should be able to fill in on the sides.

Perhaps at higher speeds it might separate but I won't know until I do some CFD analysis.

Attached Thumbnails
Click image for larger version

Name:	Angles.jpg
Views:	82
Size:	98.5 KB
ID:	3022  
__________________
http://benw385.vox.com/
'Blog' on the open source electric motorcycle project.

Please come visit and comment!
  Reply With Quote
Old 03-26-2009, 04:46 PM   #7 (permalink)
Master EcoModder
 
aerohead's Avatar
 
Join Date: Jan 2008
Location: Sanger,Texas,U.S.A.
Posts: 14,525
Thanks: 22,541
Thanked 6,714 Times in 4,254 Posts
Toying

Blue Bomber Man,start thinking about your body cut lines,how the canopy will open and hinge placement,potential interference,binding.It will affect your ingress/egress,where things pivot,hardpoints for support structure,collision protection,energy absorption, and all your human factors kinda stuff.Also,when you lay windscreen glass down at really radical angles you can end up with internal cabin reflections which inhibit your ability to see out.If the software will allow overlays 'n such,begin with yourself inside the car,and engineer from that point outward.And bear in mind any and every conceivable function you'll do in there,including the event of emergencies.It's quite the puzzle! Like your images!

  Reply With Quote
Reply  Post New Thread


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
Study (model) of various aeromods affecting a Porsche 914 wyatt Aerodynamics 27 08-29-2013 02:41 PM
Aeromodding in the 1930's: 38 mpg, 70 mph Model T MetroMPG Aerodynamics 42 05-29-2012 12:08 PM
Suggestion Model Specific Forums RabbitM Forum News & Feedback 8 09-13-2010 05:52 PM
Concept designs pmander Introductions 3 03-11-2009 10:22 PM
Strangeness: 3 different EPA ratings for Metro's last 3 model years MetroMPG General Efficiency Discussion 0 12-02-2007 08:51 AM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2022, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com