Enclosed trailers - Wind drag

If you've towed, or tow an enclosed trailer.... we're all familiar with wind drag. There's no eliminating it, but just would like to lessen it if I could.

V-nose's help some up front, but then there's the tail end. I've been seeing more & more semi trailers with the 4 panels (upper, lower, and sides) attached to the rear doors that supposedly reduce the air pocket that causing the drag, or suction as you could call it.

I'm thinking of trying it out with some cheap panel board coated with line-x, or something, to stiffin' it up.... yet keep light.

Anyone experimented doing this on there enclosed trailer by chance? If so, what were your results?

Thanks!

 

You see it on semi trailers because they drive millions of miles and every fraction of mpg counts. Unless you are also driving millions of miles you'll spend more than you ever save. But hey, have fun with it.

 

Probably cost $20-$30 to do. Nothing elaborate.

 

You sound like this guy.

 

Google hypermilling. Those guys go nuts for aerodynamics and driving tips to improve mpgs. Best thing to do is go 5mph slower.

 

I'd rather improve aero than do that.

 

While you are at it you can try dimpling your truck and trailer. If it works for golf balls it should work for towing.
I suggest one of these. Please post pics when you are done

 

Shervin surely has the answer. I imagine some discriminatingly crushed beer cans tacked to the trailing edges to induce vortices, leaving the barn doors or ramp partly open and stretching a tarp across the opening with a less than adequate tent pole strategically placed to support the bellow, 100psi in the tires and back off the bearing nuts another 1/4 turn, too.
...piece o' cake.

 

1/4" Corrugated (Coroplast) plastic might be a good choice, drywall screws screw right into the ribs for super light assemblies. Its about 20$ for a 4x8 sheet. The problem will be measuring the results.The gains will be fairly small and hard to discern from a host of other factors.

 

they have a discussion forum for this hobby... its entertaining to troll.

 

Anyone tried these?

 

I have not had a chance to try Nascar Bob's pitstop challenge sponsored by Dewalt

 

Maybe you should.

 

I'd go with Lever.

 

In case finer points of engineering are lost on you, we're modifyin', not fixin'. That's a job for Shervin, hands down.

 

You may not be aware that Lever specifically studied this field and got one of his PhD's in highway drag reduction.

 

Per google, the side skirts, in conjunction with the aero tail fins, can yield up to 10% better fuel economy on a semi truck. Ironically, i got curious during a drive home from the track and looked it up while JB drove the Sprinter.

I highly doubt that 10% would translate on a smaller vehicle, for a number of reasons... 1) your vehicle is pushing less air, so the drag you're reducing is lower to begin with. 2) Semis are getting 4-8 mpg, so "10%" improvement for them is .8 mpg in a best-case scenario. Because your vehicle (hopefully) gets significantly better mileage to begin with, you're going to be lucky to see a 5% improvement.

I am all for a little experimenting to see what works with aerodynamics, but you're going to have a real hard time doing that without a wind tunnel. A small scale model with water and some food coloring might be a fun experiment.

All that said, the real solution is to drive slower.

 

Yes, I stuck them to the top and sides at the rear of my trailer. Didn't really notice much of an improvement, but as ScottyRock said earlier, it might be fractions of whatever that only becomes appreciable after having driven an inordinate amount of miles which I really am not doing with my trailer.

 

It's an oldie but a goody and totally appropriate for this response

 

well the other caveat... the wind may not always be blowing in the direction youre traveling.