Good News Everyone - Page 2 - Fuelly Forums
Go Back   Fuelly Forums > Fuel Talk > Aerodynamics
Search Today's Posts Mark Forums Read
Thread Tools Display Modes
Old 11-18-2007, 05:05 AM   #11
Registered Member
Join Date: May 2007
Posts: 200
Country: United States
Originally Posted by cfg83 View Post
Nerds laugh at me -

Thanks, I found this one :

Saturn Sedan Compact Car
Attachment 1086

It looks like a 3rd Gen body, but that's close enough. Changing it to be a wagon should be easy, just extrude the rear window to the end. I am guessing that it is smooth on the underside.

Is a "3ds max" file format compatible with what COSMOS needs?


Once I get my computer up and running ( or just create a new one ) I'd be happy to modify that model.
Today is the last day of my vacation, so I will be without a computer or internet from now on.
Hopefully I can fix my system soon.

My mother has the same car as you- but the coupe version ( the version that you have a model of. )so I will have plenty of reference to go from.( It is even the same color )

Nerds laugh at me is offline   Reply With Quote
Old 11-18-2007, 05:30 AM   #12
Registered Member
ZugyNA's Avatar
Join Date: May 2006
Posts: 587
Country: United States
Here is a simple idea to test?

Reverse airfoil vs almost blunt:

"I had a Plymouth Reliant Station Wagon, with a 2.4 L engine and an automatic transmission. We used it to go camping quite a lot, so I built a car top for it, the length of the top and about 20" tall. I built the front to match the angle of the windshield and just squared off the back.

In terms of packing and hauling it worked really well. I had to put air shocks on the car to get it back to level, but after that it worked great.

The only problem was that with the heavy load of people and equipment filling the entire car and car top, I would get up to about 56-58mph and then it would be like a hit a wall. If I had a really long run, I might have been able to get it up to 65mph.

One year, on a annual trip to Death Valley, in December, I wanted to take some fire wood with us, since you can't get any their. However, we were out of room, so I put a tarp on the top of the car top, stacked a pile of wood about 10" high and about 3 ' long, at the back end of the car top.

In previous years I would get about 17-18mpg, with the car top on. My gas mileage went up to about 22mpg. Additionally, when I got up to about 57mph, I didn't seem to hit the wall, like I had previously.

So I got some cardboard and fabricated a shape to put on the top of the car-top/carrier. The shape was a reverse airfoil, upper half, placed across the top of the car-top/carrier. With this shape, I was able to drive at a higher speed, I could pass other car's at 65 and so forth. I also was able to get 22mpg-25mpg.

I gave the car and car top to my parents. They made a trip with it, with 5 full size adult's and with the car packed with everything from the kitchen sink to who know's what. I asked my dad how he thought they had done on mileage and he said he had only checked the first tank of gas, which didn't make any sense, because he was always checking mileage, on trips. He said that on the first tank they got 25 mpg and he was dumbfounded. He said he didn't think anyone could ever get that kind of mileage, with that kind of load, in a car with that size of engine. So'o he quit checking it because he didn't want to try to figure out how it could be getting that, in case it was because of some etheral experience or cause he might jinx or upset the balance of, if he tried to figure it out, to closely.

I believe what was happening is that the huge box shape on the back side was basically creating a huge vacuum behind the car and that the reverse airfoil shape caused the air to be accelerated from the top of the car back down behind the car, breaking up or releasing the vacuum effect's on the car. In either case, their was definitely a force beyond just frontal surface area, which was really dragging the car down, as the speed's went up."

+ 22 to 39 % mpg gain

This wagon has a sloped back end to it...around 70* rather than 90*?

This involves increasing frontal drag substantially but still seeing substantial reduced drag overall.

I'm actually trying to test this idea with a small wagon by using some leaf filled bags, a section of waferbaord and a tarp over it all to try to duplicate this shape partially. Looks like I'm going on a trip.

Leading the perpetually ignorant and uninformed into the light of scientific knowledge. Did I really say that?

a new policy....I intend to ignore the nescient...a waste of time and energy.
ZugyNA is offline   Reply With Quote

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
MPG versus air temperature and Altitude MensaMike General Fuel Topics 6 06-21-2011 05:16 AM
can receipts be entered in any date order? mauirixxx Fuelly Web Support and Community News 9 08-29-2008 02:21 PM
How some 9 pound alloys changed my life SVOboy General Fuel Topics 43 08-11-2006 03:41 PM
What is Hypermilling? GasSavers_Ryland Hypermiling 24 05-29-2006 07:05 AM
"active" aero grille slats on 06 civic concept MetroMPG General Fuel Topics 21 01-03-2006 12:02 PM

Powered by vBadvanced CMPS v3.2.3

All times are GMT -8. The time now is 10:14 AM.

Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2016, vBulletin Solutions, Inc.