06-23-2009, 06:13 PM
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#1 (permalink)
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Master EcoModder
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Teardrop roof for boxy SUV?
The relatively small chamfer between my Cherokee's windshield and roof makes me think that airflow separates up there, creating a lot of extra drag. Could that effect be reduced on vehicles like this with a teardrop shaped / half aerofoil roof? Yes, the frontal area would increase, but I think it could be worth it.
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06-23-2009, 06:17 PM
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#2 (permalink)
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Master EcoModder
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A small tail could also be grafted on
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06-23-2009, 06:44 PM
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#3 (permalink)
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Master EcoModder
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wow! It looks like you have welded a parking garage to the top of you Jeep. ;-)
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06-23-2009, 06:50 PM
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#4 (permalink)
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Master EcoModder
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roof
My opinion would be to leave the roof as is,and go after the wake.I'm going to try and give you a link.It's a photo of a Rabbit with a similar roofline and completely attached flow,and then you'll see the enormous wake that's robbing you at the gas pump.-------------------------------------------------------- http://ecomodder.com/forum/member-ae...ere-money.html
MODERATOR EDIT: Added by cfg83 :
Last edited by cfg83; 06-23-2009 at 07:00 PM..
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06-23-2009, 06:53 PM
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#5 (permalink)
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Master EcoModder
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Quote:
Originally Posted by aerohead
My opinion would be to leave the roof as is,and go after the wake.I'm going to try and give you a link.It's a photo of a Rabbit with a similar roofline and completely attached flow,and then you'll see the enormous wake that's robbing you at the gas pump.-------------------------------------------------------- http://ecomodder.com/forum/member-ae...ere-money.html |
Whoops! that put the whole enchilada up.Go to "other vehicles,page-2,down to line 5,and over 3 photos to see Rabbit wake. |
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06-23-2009, 06:56 PM
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#6 (permalink)
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Master EcoModder
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It looks like it should clean things up a bit.
Break out the cardboard and duct tape and find out !!!
Adding a partial kamm like metrompg should help as well. I'm trying to get SHMBO to let me add one to her SUV.
Keep us posted as to how much improvement you get.
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06-23-2009, 07:21 PM
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#7 (permalink)
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I've noticed on mine about halfway up the windshield rain drop start to flow up at high speeds. Plus more and more SUV's I've seen have that tail, so i'm guessing it's there for more then looks. It's a big project, but it may smooth things out a bit.
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06-23-2009, 07:29 PM
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#8 (permalink)
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Master EcoModder
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I'm with aerohead on this one. The wake at the back is far more detrimental than the flow separation at the front/top.
(sorry for my lame joke earlier but, look at the pictures closer) (tough crowd)  |
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06-23-2009, 09:37 PM
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#9 (permalink)
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Master EcoModder
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I'm pretty sure there is no way I could create anything that would really work. It's too big to build with cardboard IMO. I also think it would need chamfered edges to avoid creating a lot of vortices
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06-23-2009, 09:39 PM
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#10 (permalink)
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Master EcoModder
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Quote:
Originally Posted by FastPlastic
I've noticed on mine about halfway up the windshield rain drop start to flow up at high speeds. Plus more and more SUV's I've seen have that tail, so i'm guessing it's there for more then looks. It's a big project, but it may smooth things out a bit.
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You think the front is so blunt that it creates a wake that extends halfway up the windshield?
Maybe a deflector on the front would be useful too
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