Aerodynamic trailer - Fuel Economy, Hypermiling, EcoModding News and Forum

bennelson · 08-10-2008, 11:56 PM

Hey Folks,

I have a "teardrop trailer" and met another person this past weekend who also has one.

Mine

Hers is longer and more of a straight slope on the back, where as mine, and most other teardrops curve down much sharper.

Hers.

She drives a Dodge Dakota pickup truck with a V-8 engine and cap. She told me that her truck gets 16 MPG regularly, but gets 18 MPG while pulling the trailer. She also said she is a leadfoot, and we all know how important aero gets at high speeds.

Just though it was cool to see a trailer that IMPROVES FUEL ECONOMY.

She threatened to drive around with it attached all the time.

PS: I get about 27 mpg while towing mine!

MechEngVT · 08-12-2008, 09:28 AM

That's pretty cool, I like the flamed one and can see how that would reduce the wake area of a full-size truck. The roof is slanted downward a little steep but I wonder what a tuft test would look like on it. I've seen quite a few camper-like trailers with the teardrop shape and I saw on TV where that style has been around since around the 1930s before roadside hotels were common.

I saw another link with a "streamlined" car hauler that was designed by a very reputable race car designer who built the original Cobra Daytona coupe. It can be seen at:

http://www.saac.com/files/orca.pdf

Note the PDF file format.

Remember this is intended to haul a race car and the general assumption seems to be that you would pull this with a pickup truck. There's only so much one can do to reduce the wake area and still be able to load a car and this design adheres pretty much to convention on the rear of the trailer. Also the design is somewhat limited IHMO by sticking with aluminum for the top and sides. Some fiberglass would allow better streamlining and more design flexibility. I really don't like the scallops down the sides and it looks like it turns the rear end of those scallops into air brakes. The only thing I can think that they are for is to stiffen the walls and prevent panel flexing but there are many more aerodynamic ways of doing that.

All in all it's a decent attempt but there's a distinct shortage of data to back up the design's validity. The only reason I think it's worth mentioning is the guy did one heck of a job putting a decent Kamm back on the Daytona Coupe back before people understood the importance of aerodynamics even in racing.

MazdaMatt · 08-12-2008, 10:04 AM

I wouldn't mind hauling my race car in that

I think that it would make more sense, however, to back in the race car and have a hinged roof. This way your high wing is at the front and your low hood is at the back, and the hinged roof can slope down to a taper... maybe i need to sell my cube van and start designing.

bryn · 08-12-2008, 10:36 AM

i bet her jump in mpg has more to do with how she drives, than the aero.

traveling somewhere, so more highway,

also slower acceleration, more careful braking, probably driving slower overall.

i bet the mpg would drop pretty fast on a daily commute.
it'd be nice if she had a scan guage for some a-b-a on the highway

Xringer · 08-12-2008, 11:26 AM

Quote:

Originally Posted by bryn

i bet her jump in mpg has more to do with how she drives, than the aero.

traveling somewhere, so more highway,

also slower acceleration, more careful braking, probably driving slower overall.

i bet the mpg would drop pretty fast on a daily commute.
it'd be nice if she had a scan guage for some a-b-a on the highway

Maybe she needs to do some coast test? Like that guy who found out
having a Kayak sticking out of his hatchback helped his fe.?.

elhigh · 08-12-2008, 11:35 AM

Quote:

Originally Posted by MazdaMatt

I wouldn't mind hauling my race car in that

.

Check it out, Matt's race car folds!

MazdaMatt · 08-12-2008, 11:38 AM

Quote:

Originally Posted by elhigh

Check it out, Matt's race car folds!

*sigh*... i was referring to the link to the aero race car trailer!

aerohead · 08-16-2008, 03:26 PM

bennelson,if you'll go to Darin's thread for his permanent Kammback for the Metro you'll find an aerodynamic template and description for use,which would allow you to appraise the merits of your trailer.A properly scaled photo of your car/trailer combo,placed under the template would illustrate any mods you might consider to up the performance of the teardrop.

bennelson · 08-17-2008, 10:41 AM

I am not planning on modding this trailer, but it is a really interesting idea for anyone building a trailer in the future.

Just imagine - go camping and get BETTER fuel economy driving there and back!

Will · 08-17-2008, 11:51 AM

Love the whole little trailer thing. I wonder how that would look behind my Metro. Then again I probably couldn't pull it

There's always the wife's Buick!

instarx · 08-19-2008, 03:50 PM

Quote:

Originally Posted by Will

Love the whole little trailer thing. I wonder how that would look behind my Metro. Then again I probably couldn't pull it

There's always the wife's Buick!

You probably could pull one of the smaller teardrops. I've seen pictures of them being pulled by VW beetles. Small teardrops with aluminum frames can weigh as little as 600 lbs.

Will · 08-19-2008, 11:48 PM

A Metro pulling a camper. I like it!!! I may look into this a little more.

Xringer · 08-20-2008, 12:21 AM

Quote:

Originally Posted by instarx

You probably could pull one of the smaller teardrops. I've seen pictures of them being pulled by VW beetles. Small teardrops with aluminum frames can weigh as little as 600 lbs.

Little Guy Teardrop Trailers - Travel Mate

You pull those little guys with a motor bike..

Sunwapta · 08-20-2008, 12:51 AM

This thread is great!!! Trailer aerodynamics are really interesting to me and they seem to be totally overlooked by the mainstream manufacturer even though they have such a huge impact on fuel consumption.

I have a new K-Z Spree with a fibreglass front. (I don't know how to post a picture but google image it for a look - is that big indentation on the front good or bad. Sure doesn't look good to me unless it creates some kind of frontal air bubble effect.)

And then there's the square backs on most of them - good or bad? Shouldn't there be something done there?

Christopher Jordan · 08-20-2008, 02:45 PM

Quote:

Originally Posted by Xringer

You pull those little guys with a motor bike..

Smaller scale & different motorized bike (color went crazy- dark green w/ purple + yellow trailer).

bennelson · 08-20-2008, 03:18 PM

What are know as "teardrop trailers" really aren't very aerodynamic.

I wanted to point out the crazy looking red and blue trailer pictured at the beginning of this thread because it has a different back-end than most teardrops - one that is more aerodynamic than usual.

This guy built two different teardrops - the second one with aerodynamics in mind.

I have also thrown around ideas of a generator trailer for the electric motorcycle (which could also go on the Metro, if designed right).

If I ever did create such a thing, I would definately want to build it with aerodynamics in mind.