Aerodynamic Applications

by Carroll McCormick

BLAINVILLE, Que. –A non-expert would be hard-pressed to name two improvements in truck aerodynamics in the last 30 years: cab-mounted air foils and maybe, just maybe the “anteater”, also known as the Kenworth T600, introduced to the market in 1985. This tractor boasted a 22% improvement in fuel efficiency over the straight hood conventional, and god knows how much of an improvement over the cabover, which has the aerodynamic profile of a barn door.

Oh, there have been other improvements of minor note, but the mainstream only seems to have begun working itself into a lather about lowering tractor-trailer wind resistance and reducing fuel consumption in the last couple of years.

But then, the concept of reducing aerodynamic drag does sound like witchcraft to many outside the aerospace industry and the prospect of spending big bucks on products with an uncertain return on investment (ROI) is not exactly confidence-inspiring.

“We have a very bad record in the transportation industry for technological implementation. There are very few innovators and about 40% fail when it comes time to implement new technology. We know that some of the aerodynamic products work and some don’t. That is where people are not sure: ‘what is the real value of these devices?’ People do not have the hard numbers,” explains Yves Provencher, business development manager with FPInnovations – Feric in Montreal.

Thankfully, Feric, with its new PIT program and Transport Robert, with the participation of a few other big fleets have gone for the hard numbers with carefully-controlled tests of aerodynamic products and other fuel-saving technologies on Transport Canada’s test track in Blainville, Que.

In their first set of trials, called Energotest 2007, they tested: trailer side skirts, which mount below the sides of trailers; devices that change the rear of the trailer from a box shape to a tapered shape; and aerodynamic truck fenders. Nonaerodynamic ‘fuel-saving’ products were also on trial.

The Freight Wing side skirts improved fuel efficiency by 7.2%. A similar product called the TrailerSkirt, by Laydon Composites yielded a 6.8% improvement. Two products that attach on the back of trailers, the TrailerTails, by Advanced Transit Dynamics, and the BoatTail, by Transtex Composite obtained savings of 5.1% and 2.6%, respectively. The fenders, by Meka Form, improved fuel efficiency by 1.4%.

EnergoTest 2008 gathered more data that showed improved fuel efficiency for some products and tractor-trailer configurations, but only the members of Project Innovation Transport (PIT), a group of fleets and industry partners who support the tests, have seen the full results.

Hard data just sets the stage for calculating ROI, however. Aerodynamic drag is only really of concern at highway speeds.

“As a broad rule if you go under 70 km/h, don’t even think of aerodynamics. That is not going to be your problem,” Provencher says. Garbage trucks will never be slicked out like speed skaters and in-city fleets will have to look to non-aerodynamic technologies for top fuel-saving ROI.

Even for over-the-road fleets, a good ROI is not assured. The fuel savings on the track may be 7%, but in the real world, the trailer may be operating at 100 km/h (the speed at which the products were tested) only 80% of the time. Then you have to figure in how long your trailers are parked. There is also the lifespan of the product to consider.

As Provencher notes, “This is why people have had a hard time implementing technologies in general. You have to do the calcula- tions right.”

On the plus side, on-board computers are already collecting all the data fleet managers need to calculate average speeds, the percentage of time the trailers are rolling at over 70 km/h, current fuel consumption, trailer downtime and the like.

Even when a fleet decides to buy a product, it has to be installed correctly.

“We see fleets that are installing skirts, but they are installing them the wrong way. We tested skirts, and depending on the angle the trailer skirts are installed on the trailer, the fuel savings can be from zero to 7.5%,” says Provencher.

For the first time in Canada, I might dare to claim, fleets have in PIT a place to go for good data and expert support in calculating ROI and obtaining installation advice. PIT, created immediately after Energotest 2007, is a subsidiary of Feric, which has some 25 transportation experts on staff.

“The membership fee is $50 per tractor, before any tax credits. So you are only out of pocket about $30. PIT members are already finding value in this,” Provencher says. “There is value in testing these products, but implementation only happens if testing is supported.”

Otherwise, fleets can go it alone, running their own trials and ciphering their ROIs. Logistics Transwest in Lachine, Que., for example, reports an 8% improvement in fuel consumption with five trailers it outfitted with trailer skirts last April; the majority of its trucking is long-haul to the southern US. Michael Morin, responsible for optimizing fuel consumption, says, “I was already convinced before (Energotest 2007) that the products were worthwhile.”

He is poised to install trailer skirts on 78 trailers if he gets a Transport Canada ecoFreight subsidy. And if he doesn’t?

“It is certain that we will win with (the trailer skirt) products. If we do not get a subsidy, we will install the skirts (anyway), probably fewer at a time, but we will install them,” Morin says, adding, “We want to participate in Energotest 2009.”


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