Aerodynamic Devices Drive Sustainable Productivity
Sustainable productivity is about finding ways to both cut costs and help the environment. By saving fuel and reducing Praxair’s carbon footprint, the new gap fairings and aerodynamic skirts North American Industrial Gases (NAIG) is testing on its bulk distribution fleet are designed to do exactly that.
“Fuel is one of our largest distribution-related costs, and each of these devices alone has the capacity to improve fuel economy by up to seven percent and perhaps more when used together,” said NAIG Value Stream Leader Bob Dombrowski, who has been investigating ways to reduce fuel consumption from a productivity standpoint.
“That means they have the potential to substantially reduce our annual fuel costs, depending on driver routes and the price of fuel, which has been rising at the moment,” noted Bob.
How do they work?
There are several areas where it is possible to reduce wind resistance on tanker trailers, and Praxair is starting by tackling two: the gap between the tractor and the trailer and underneath the trailer. The aluminum gap fairings are designed to limit the wind resistance between the tractor and trailer and the composite skirts prevent wind from pooling under the trailer.
“Gap fairings are not new,” said Research and Development Engineering Consultant Barry Minbiole. “You see them used on box trucks all the time, but rarely on tanker trailers. That’s because box trucks are all generally about the same size, so original equipment manufactures can make one size for all. Since tankers only make up about 10 percent of the trucks on the road and vary in size, there has been little effort to manufacture them for tankers. We want to change that for our fleet.”
Where are they being tested?
“It’s important to point out that we are still testing both devices,” notes NAIG Operations Manager Tim Johnson. “We need to get more data points before we roll them out extensively. Currently, NAIG is testing the gap fairing on two nitrogen tractor trailers operating out of Laporte, Ind. and the aerodynamic skirts on two units operating out of Garfield, Utah, and two in Ohio, Canton and Oregon/Toledo. “So far,” said Tim, “we’re seeing the expected fuel savings.”
With Praxair’s strong emphasis on safety and operational discipline, the teams need to fully understand how these aerodynamic devices, which are very common in the trucking industry, affect drivers. “The development teams are collecting the operational feedback to accompany the quantitative improvements, to ensure we evolve to safe and practical solutions,” said Barry.
The teams have also been working with the device suppliers to incorporate the improvements suggested by drivers, including enhancing visibility for the tractor device and improving access to the pressure building coil for the trailer skirts.
“For instance, we have been experimenting with transparent panels on the gap fairings,” noted Barry. “These help improve the view out the passenger side when a driver is backing up the vehicle. Initial feedback from the drivers has been positive.”
“Since there’s no commercially available proven solution for our particular needs,” explained Tim, “input from our drivers, mechanics and supervisors is critical to ultimately creating devices that provide the fuel economy benefits we want without compromising fleet safety.”