This tale of two trailers proves that there’s savings to be had in some of the unlikeliest places.
By Today’s Trucking Staff
A team consisting of Manac Trailers, Cascades and FPInnovations has developed a standard van trailer that can reportedly cut your fuel consumption by six percent.
FPInnovations is the Quebec-based, private-sector, not-for-profit research center. Manac is one of Canada’s most respected trailer manufacturers and Cascades is of course the paper-products-and-recycling giant.
In September they announced that thanks in part to a $50,000 grant from Quebec’s Ministry of Transport, (MTQ), they have produced a 53-ft trailer that boasts a 12-percent reduction in aerodynamic drag.
The trailer doesn’t appear radically different from standard vans.
FP Innovations’ Director Yves Provencher told Today’s Trucking that Cascades set the design criteria.“We wanted to keep the same volume, the same door sizes and the capability to back up to the docks so that the trailer can be easily loaded,” Provencher says. “To save cost for the prototype, we used an existing trailer.
“The front top corner of the trailer is rounded. The modifications were only made in the top part of the trailer. If the performance of this trailer proves to be positive, a new design would be totally redone, including the suspension.”
The wedge design means the floor is sloped by five inches but capacity remains the same. Other advantages: The new trailer meets American and Mexican as well as Canadian regulations and offers a possible 14-ton reduction in CO2 emissions.
FPInnovations estimates the North American trailer market for this sort of van is about 64,000 units per year, worth over $1.5 billion.
According to Marc Berthiaume, Manac Engineering Department Manager, “Manac is always interested in participating in initiatives leading to the development of eco-energy technologies, especially with a team of partners as dynamic, painstaking and inspiring as this.”??
Adds Provencher: “Our team has put together the best knowledge and cutting-edge technology for the benefit of the transportation industry—in this case, the trucking sector.”
The next step is to take the trailer out of the wind-tunnel stage and compare its performance to standard three-axle trailers in actual use.
At the same time as FPInnovations was working up its scheme, another trucker, Ryan Viessman, of Gary, S.D., was dealing with a different trailer dilemma.
Viessman’s fleet, CVI, runs about 70 pneumatic bulk trailers that haul refined sugar, flour, and starches from shippers throughout the Midwest.
Side skirts and other fairings—so effective at improving the aerodynamics of dry vans and reefers—generally aren’t practical for pneumatic bulk trailers. They’re hard to install without interfering with access to piping, outlet valves, and other equipment, and they can add several hundred pounds to the weight of the vehicle.
“Bulk fleets everywhere face the same problem,” Viessman says. “How do we bring aerodynamic improvements to the trailer that are simple and low cost, have zero impact on our operations, and require little or no maintenance?”
The company challenged its long-time trailer supplier, Polar Tank, to find the answer.
Trailer aerodynamics directly affect your total horsepower needs and, therefore, your fuel economy, says Duane Plumski, Research and Development Engineer, Polar Tank Trailer. The typical van or refrigerated trailer accounts for 65 to 75 percent of a tractor-trailer combination’s total aerodynamic drag.
“A pneumatic trailer is more streamlined than a flat-fronted trailer, but there are elements like external rings, handholds, and piping that disrupt the airflow,” Plumski says. “We analyzed virtually every aspect of the trailer to see what we could do to reduce the aerodynamic drag and potentially improve fuel economy without affecting capacity or operations.”
He and Polar engineers put their 3D modeling tools to work. “With our software, we can design, visualize, and simulate the trailer’s drag effects before it’s built,” Plumski notes. “We can predict how design changes will affect not only fuel economy but
the strength, durability, and operation of the vehicle.”
To improve aerodynamics, Polar engineers first focused on the overall shape of the trailer, starting with the front face.
The front of a trailer accounts for approximately 30 percent of its aerodynamic drag. Polar engineers lowered the tank’s front end-cone and tipped it forward slightly to reduce the profile and soften the impact of air coming over the tractor.
They also reduced areas along the trailer that disrupt the air flowing over the trailer.
One obvious source of drag: the external side rings, which wrap vertically, like ribs around the aluminum tank. The benefit of external-ring bracing is a smooth interior; in contrast, a trailer that’s smooth on the outside will have struts inside the tank for structural support.
“In our experience, cleaning trailers with internal ribs is a major issue,” says Joey Viessman, who manages the company’s fleet in Renville. “Product collects around the bracing and makes it hard to unload or clean out.”
Plumski says his engineering team made sure those transition points between the internal ribs don’t hinder the ability to empty the trailer completely.
“Our priority was to ensure that no change would alter the capacity of the tank, the distribution of the payload, or the ease of loading or off-loading product,” he says. “We preserved the round sloping interior surfaces and designed the ribs so that the trailer will empty cleanly but you get the aerodynamic benefit of the smooth exterior.”
To date, CVI has two aerodynamic pneumatic trailers from Polar and has ordered four more. They haul an average 55,000-pound payload on round trips of 500 miles a day behind day cab tractors.
The result: all things being equal, the new Polar trailers average roughly 0.3 mile a gallon better than the externally ringed trailers.