Anyone 'aeroing' 18 wheelers?
 

I'm designing some aero components for the trucking industry. These things average 6 MPG and run up to 300,000 miles per year so U can see the payback is quite quick.

Happy AERO-ING

Yes: https://www.llnl.gov/str/May03/McCallen.html

Transport trucks are so massively un-aerodynamic, and consume so much fuel, I'm surprised the owner/operators aren't doing it themselves.

Nose Cone
 

Been twenty years since I did this one. It was an add on nosecone for the front of the cabover style truck which fit over the flat front of the tractor above the bumper. I figured any optimization of frontal surface would be better than the flat front face of the cabover. Learned alot about Aerodynamics. On 18 wheelers it's all about yaw angle Y'all.

Basically it wasn't that effective. It did show a small amount of improvment in the test trucks fuel efficiency. I was told by the Arkansas based company who tested it, if Diesel fuel ever went to $2.00 a gallon or more they may well consider it.

Again, that was in 1988, Diesel fuel, I think, was around $1.00 a gallon. This company no longer runs the International Cab Over style tractors either, much to the relief of drivers.

Good luck Mandilon on your Aero mods you are developing for big rigs. I have read that some business's are getting Federal Grant money for this. I sure wish they had some grant money for the light trucks!

Brett

Here's some more to go with this.

As you can see there has been a lot of work done. Some guys work quite hard on their tractors.

What defeats these efforts is the "disposable" nature of the trailer. A truck often takes a trailer to a dock and drops it off and goes out into the yard to pick up another going elsewhere. He/she has no investment in the first trailer so why worry about it.

Also, a lot of what look like van-type trailers are actually containers on modified flat beds. In order to maximize the number of containers on the ships, the containers maintain a very regualr and flat silhouette.

Thanks to sheer volume, Wally-World can dictate. Nobody else can.

Yea I see the problem but... Is there a way to make the side skirts fairing etc bolt on or quick disconnect. The cab mods would stay the same and if most trailers are alike you could make the side fairing swap in about 15 minutes if there were some kind of universal mounts.

Aero-mods are good, but, slowing down is better.
The P.O. has a fleet that is fairly new. Our (here in Norf.) fleet is only 2 years old. The new trucks are better with mpg than the old ones were. Yes the new ones are slightly more aero. But the main difference is the new trucks are regulated to 60 mph. The old trucks average was 9 mgp. Unregulated, go as fast as you can. The new trucks average 12 mpg. Regulated @ 60.
We have 2 of the old style here for spares, when compared side by side there is not much difference in the shapes.
That's my $.02 .S.

I tend to be in awe of just how efficient they are with being built like barns.

In a 53' trailer there's something like 3950 cubic feet of space and a 60,000# payload and with the right truck hauling it they still somehow eek out a handful of miles per gallon at the very minimum.

That's got to be equal to the loads of about 40 to 80 cars... which effectively makes them the equiv of a reasonably loaded car getting 200 to 400 MPG.

BTW, they should all have protective side-fairings for the sake of pedestrians, cyclists and cars... very few in North America do.

Nasa did
 

Nasa tried at aero-ing hope this helps you in your endeavors of helping the truckers.

I know this isn't totally related to the thread but it was too cool not to share!!!


http://images.google.com/imgres?imgu...US219%26sa%3DN

"Here's some more to go with this."
 

Web domain lost (to the thieves at hostway.com).

Bought TruckingInOverdrive.com

The above URL has been corrected.

THX & God Bless Y'all!

I did a search for you on this site using the keywords " 18 wheeler , semi, and rig " but I'm not getting any results. ( confused )
The reason why I did this, is that there are several posts already devoted to this. We have discussed this several times.
Sorry I can't seem to be able to use the search function correctly, but if you search through the 'aerodynamics' part of the forum, you will eventually see several of these postings.

( One thread - mine actually - comes to mind entitled 'Accordian kammback for big rigs ?" It's long dead BTW.)

Good luck

http://ecomodder.com/forum/showthrea...-1-a-7201.html

http://ecomodder.com/forum/showthrea...rigs-6090.html

http://ecomodder.com/forum/showthrea...-van-3948.html

http://ecomodder.com/forum/showthrea...kers-1689.html

a conventional versus cabover is about as good as it gets...and even then, the only noticable thing, not even fuel mileage, was cross winds are gentler in the long nose (or known as "conventional", beciause conventuional is that obviously "normal", caboivers are a cheat to poor basturds tortured to drive them by capitalism.). It is a case of set power so beyond the quibbling of aerodynamics of vehicles just roaming the earth like giant dinosaurs in superiority..god didn't give a dinosaur a ricer wing either.

I have been around trucking my whole life, and in places that knock a rig over in the wind. Keep your silly areodynamics, and better make it steel. there ius a forward aero of conveneince and comfort, for driver and surrounding machines..the fule? it does so next to nothing through these changes...the aero is for people more than the truck.

http://ecomodder.com/forum/showthrea...ies-10398.html

http://ecomodder.com/forum/showthrea...bus-10004.html

http://ecomodder.com/forum/showthrea...uv-8918-3.html

http://ecomodder.com/forum/showthrea...-7-a-6678.html

You're right.
Brilliant !

On conventional cabs, using Freightliner as an example, they offer a aero and a "classic" body design. Most drivers I know say that with equal trucks the biggest difference they see between the 2 is about 1 mpg and that's in strong (35mph +) Headwinds.

AS far as side skirts etc, I have an uncle whos company spent a couple years carefully evaluating the different systems and they found about zero economy savings vs the cost of maintaining the system. Did not pay for itself at all.

They played with LNG boosted diesel engines as well, and same thing, the maintenance cost overwhelmed the small fuel savings, except when you had a truck who's route was all steep hills, then the power boost of the LNG kicked in and helped the fuel burn on the long 6% rocky mountain grades. But even that simply did not pay.

They also invested in a couple hybrid tractors, and the battery life killed those... They were wearing out the batteries in like 6 months and the trucks needed like 48 batteries at 400 bucks apiece... NO way to make it pay...

Dave

http://ladybugtrucking.com/
 

Here's my design for my future reefer cabover 'straight truck.' The box portion will be about 28' to carry a cargo capacity of about a 20-22' footer.


I will test this against a 'conventional-designed' rig. The body will be mounted on a modified roller skate platform.

I'm also going to 'plastic vacuum form' this design for individuals that would like to use it as 'a starting base' for their own ideas.

I'll be updating/uploading photos to Lady Bug Trucking , ladybugtrucking.biz - Registered at Namecheap.com or ladybugtrucking.us - Registered at Namecheap.com

http://ladybugtrucking.com/img/wellmeetinla-re.jpg

GOOGLE (forget about BING): "green trucking concepts"

I am friends with a few owner/operators. They want HP in their Freightliners. I asked about side skirts and the answer they gave me was that they get blown around more with the added surface area. They could give a hoot about super singles since it costs money to take off good tires.

Some of these guys treat their trucks like hot rods. They want good looking trucks that go fast.

Here's a link to a thread with a post by Bondo about his patent (8,408,626) on reducing drag on semi trailers: http://ecomodder.com/forum/showthrea...-20744-11.html. They must be in production by someone because I've seen 2 or 3 going down the road in the last six months. Course, it wasn't until I found his post that I read the patent and understood how they worked. The first one I saw, I actually thought it was some kind of weather shield for unloading on an uncovered dock in the rain, sigh. Just couldn't put "aerodynamics" and "18 wheeler" together mentally :-).

AirFlow BulletTruck Project
http://ecomodder.com/forum/showthrea...tml#post289346

Thanks, Nemo, for the BulletTruck link, great stuff there. I also wanted to give a link to an article at another site: Getting Better Fuel Mileage (Trucks) • Speed Talk. This site is primarily oriented towards building drag race engines but there is a lot of discussion about engine efficiency and some aero. One interesting tidbit from this article is the comment that cab to trailer front spacing needs to be under 24" and ideally 15-18". By 24" the drag has risen noticeably, and at 48" the drag is the same as two independent vehicles. Has anyone seen any other guidelines on this? That poster doesn't give a reference.

I saw one of these the other day on the freeway and snapped a photo (attached).

Foldable tail extension!

If those drawings are to scale it looks like when the gap is one tire diameter the Cd has risen about 40% of the total loss, and at 1/2 a tire diameter the Cd has only risen 12% of the total loss. So if the tires are 36" tall (my guess, too lazy to go look), that would be a gap of 18" for the 12% of the total loss, and 36" for the 40% of total loss, which compares pretty well with the 24" max guideline in the article I linked. Thanks, freebeard.

spacing
 

Here's one study
http://i1271.photobucket.com/albums/...ead2/Scan3.jpg
Here's one from GM illustrating the effect of gap-fillers
http://i1271.photobucket.com/albums/...ad2/image5.jpg
http://i1271.photobucket.com/albums/...ad2/image4.jpg
http://i1271.photobucket.com/albums/...ad2/image3.jpg
http://i1271.photobucket.com/albums/...ad2/image2.jpg
http://i1271.photobucket.com/albums/...ad2/image1.jpg
http://i1271.photobucket.com/albums/...ead2/Scan2.jpg

Oops, need to correct a mistake I made in post #21 above - the patent by Bondo I listed is for his aerodynamic pickup truck bed extender. The patent on reducing drag on 18 wheelers with the box extension and vortex generators is by William Basford, number 6,959,958. Sorry bout that.