Posted on 04/17/2008 1:33:38 PM PDT by Red Badger
Creating an improved aerodynamic shape for heavy-duty truck trailers by mounting sideskirts can cut fuel consumption and emissions by up to 15%, according to road testing by the Dutch research partnership PART (Platform for Aerodynamic Road Transport). PART is a partnership between TU Delft, TNT, Scania Beers BV, FOCWA Carrosseriebouw, Ephicas, Kees Mulder Carrosserieën, Van Eck Carrosseriebouw, Syntens, Squarell Technology, Emons Group and NEA.
Sideskirts are plates which are mounted on the sides of trailers, primarily with a view to underrun protection. The new aerodynamic design of the sideskirts substantially reduces the air currents alongside and under the trailer and thereby also the air resistance.
Initial driving tests with a trailer equipped with the aerodynamic sideskirts over a straight stretch of public road revealed a cut in fuel consumption of between 5% and 15%. Subsequent research comprising long-term operational tests by TNT displayed a fuel reduction of 10%.
These results confirm calculations and findings from the wind tunnel tests that had established that the observed 14 - 18% reduction in air resistance led to 7 - 9% less fuel consumption. In practice, the figures are in fact even better.
PART expects that the cost of fitting aerodynamically-shaped sideskirts will be recouped within two years. Furthermore, the sideskirts can be fitted to approximately half the trucks currently in use in the Netherlands as the skirts can also be retrofitted.
In 2005, 10,000 new trailers were taken into use in the Netherlands. With an average fuel consumption of 30 liters per 100 kilometers [7.8 mpg US], that translates into 750 million liters of diesel consumption in the Netherlands each year. We can cut fuel consumption by 5% or more for 50% of those trailers. That means a reduction of 50 million tons of CO2 emissions a year. This research can therefore result in a substantial, structural contribution to cutting fuel consumption and an annual saving of tens of millions of Euros, next to that cut in CO2 emissions by the road transport sector.
Together with this sector we have created a practical platform for further research and development, but we still need active government participation. Just obtaining permits for all the road tests has involved a huge amount of time, energy and frustration. The next step is realizing a practical partnership between the government and industry in order to put the solutions into practice. —Prof. Michel van Tooren of TU Delft’s Aerospace Engineering faculty
Road tests have also already been initiated on boat tails. These constructions on the rear of a trailer ensure a reduction in the wake—the vacuum and air currents which arise when the trailer is moving. In theory, a boat tail could also mean a cut in air resistance of 30%, with a fuel reduction of 10 - 15%. These road tests should also confirm the earlier, highly positive results from the windtunnel.
Boat tails, however, are limited in practical use, in particular when loading and unloading—safety aspects and problems with exceeding maximum vehicle sizes prevent these being used for many types of vehicles.
Sideskirts my behind. Look at the (lack of a) gap between the cab and the trailer. I’ve seen Popular Science articles from the 1970s showing that closing that gap will save a bunch of drag and fuel. The problem always has been how to turn...
This 
won't get you the 10% fuel savings mentioned in the article.
>>Initial driving tests with a trailer equipped with the aerodynamic sideskirts over a straight stretch of public road revealed a cut in fuel consumption of between 5% and 15%. Subsequent research comprising long-term operational tests by TNT displayed a fuel reduction of 10%.<<
>Sideskirts my behind. Look at the (lack of a) gap between the cab and the trailer. I’ve seen Popular Science articles from the 1970s showing that closing that gap will save a bunch of drag and fuel. The problem always has been how to turn...<
There is no mention of turning. They specifically say “over a straight stretch of public road”.
The last time I saw it on the air was when they had it shooting newspapers on the Chris Elliot show. Oh how the mighty 12 wheeler has fallen!
If you notice there is nothing to keep the rain from blowing out the sides of the tractor. All that air and water has to go somewhere. Out the sides is where it is going to go. Even if you blow it out the back it will still create a ‘cloud’.
Ever look at a moving van going down the road? They sit nice and close to the ground. They get better milage than a rgular freight rig for two reasons. The load is lighter and they are more aerodynamic shaped.
There must have been two of them at one time, since they appeared on screen together in Damnation Alley. I wonder what ever happened to the other one.
Yes, used to see that and the Batmobile sitting at George Baris’ lot there along side the 101. About the only worthwhile view along that part of the Hollywood Fwy.
Darn. I hate that cloud - it is BLINDING.
When you think about it, it is the worst hazard you can encounter on a highway.
It didn't. You'll find 50 year old diagrams in first year aero engineering books describing this. But it's hard to implement in the real world and the benefit is easily degraded by road and weather conditions.
Kevlar??? Are you kidding??? Like they could afford to do that. Carbon fiber is also extremely expensive. After weight, cost, cost, cost.
http://www.hankstruckpictures.com/pix/trucks/archer/2003/may09/mackie_fl_sml.jpg
http://www.hankstruckpictures.com/pix/trucks/archer/2005/jul03/premiere-coe_sml.jpg
http://www.hankstruckpictures.com/pix/trucks/jim_groeneweg/atlas_argosy03_sml.jpg
http://www.hankstruckpictures.com/pix/trucks/archer/2005/sep02/tippet-kw-1_sml.jpg
Let me explain how to drive through it.
When you are still behind the truck in the passing lane, you can see through the water because your windshield wipers aren’t yet trying to fight it.
When you are beside the truck in the cloud the air is coming from every direction and the wipers cannot keep your windshield clean no matter what happens.
So while you are behind the truck, that’s when you have to determine if there is any reason where the trucker might have to or want to change lanes, such as he is gaining on the vehicle in front of him or there is an onramp coming up.
If both of those are negatives then increase your spead and get through the windy area as fast as you can safely do it using the side of the truck as your guideline to where your highway lane is.
Myself, I use the trucks as safety indicators to tell me what’s happening further down the road than I can see. If all the rigs start slowing down, not necessarily using their brakes, you can bet there is a mess ahead. If they are cruising that’s when I sit back and cruise too.
The worst hazard you can encounter on a highway IMO is black ice.
About 10 or 15 years ago Roger Penske had a truck and trailer for hauling his Indy race cars that had the full aero treatment. Low skirts on the trailer, no gaps between the truck and trailer, sloped top between truck and trailer as well as low sides on the truck and sloped nose. Was all custom and really looked wild. It saved quite a bit of fuel.
why didn’t you show him what WE drive?
http://images36.fotki.com/v1155/photos/2/231133/6099702/AndysTruck110-vi.jpg
http://images33.fotki.com/v1116/photos/2/231133/6099702/AndysTruck121-vi.jpg
http://images36.fotki.com/v1155/photos/2/231133/6099702/AndysTruck128-vi.jpg
http://images33.fotki.com/v1115/photos/2/231133/6099702/AndysTruck075-vi.jpg
aerodynamics isn’t really at the top of my priority list...
i thought I was the worst hazard on the hiway...
CF isn’t as expensive as you think it is, especially if you’re just making sheets of it.
“The worst hazard you can encounter on a highway IMO is black ice”.
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Ya’ll come down to Pima County and watch overloaded slavers wallowing across every lane of I-10.
Pardon my ignorance, but what is an overloaded slaver?
That’s only a rumor you’ll have to live up too........;o)
Stay safe !
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