Among the challenges facing fleet owners is the fuel efficiency lost because of the tractor-trailer gap. While the optimal position for safety, stability, and driver comfort is a wide gap, widening the gap increases aerodynamic drag and fuel consumption, especially at speeds greater than 40mph. The most common solution to reduce drag in the gap is to draw the trailer tight to the tractor and to deflect air movement away from the trailer edges using side cab extenders. Narrowing the gap creates gains in fuel efficiency, but it compromises safety and driver comfort, as well as increasing operating costs.
The AeroWall literally fills the gap with an affordable, tractor-based, aerodynamic solution that improves fuel efficiency and road safety. It works automatically with no distraction to the driver. It’s there when needed and out of the way when it’s not. Because it is tractor-based and automated, you realize the fuel savings whenever you're driving at highway speeds. In real road conditions the AeroWall delivered an average fuel efficiency boost of 4.9% in road tests based on SAE J1321 protocols, though results varied depending on the size of the gap and the severity of cross winds.
Read more: Automated and Reliable
When fully deployed, the AeroWall closes that gap for greater fuel efficiency, improved handling and stability, and increased safety. Active intelligence ensures that the system deploys when needed and retracts out of the way when it is not. A GPS system measures speed to determine when the AeroWall is deployed and when it is retracted. The AeroWall automatically deploys at 50 miles per hour—the speed that aerodynamic drag overtakes rolling resistance as a factor in vehicle fuel efficiency. At speeds less than 40 MPH, the AeroWall automatically retracts to allow for tractor-trailer articulation and driver access behind the cab.
The AeroWall is deployed using a brushless DC motor that is powered by only the tractor’s 12-volt battery system, maintaining pressure within the AeroWall. When retracted, the AeroWall compacts into plastic boxes that are mounted on the rear of the tractor’s cab. This allows for inspections and provides access to load locks and air lines.
Read more: Improved Safety
The AeroWall improves tractor and trailer stability and safety by reducing the effects of crosswinds. Visibility is improved by reducing road spray in wet road conditions. The AeroWall gives your drivers more control of the tractor and the trailer— greatly reducing lane departures and decreasing driver fatigue caused by constant steering adjustments.
The AeroWall closes the gap and improves tractor-trailer stability by reducing the effect of crosswinds, making it easier for the driver to maintain lane control, decreasing lane departures and improving safety for the driver and other vehicles
Crosswinds without AeroWall
In still air (a rare occurrence on the highway) a tractor-trailer travel together with very little yaw variance between them. However, depending on the direction and velocity of the crosswinds yaw can exceed 10 degrees.
The most important factor related to tractor-trailer gap aerodynamics is how efficiently the vehicle deals with crosswinds and turbulence, not ambient conditions. Studies have shown the gap produces approximately 25% of the total drag. Fuel efficiency is reduced by 13% for every 10 mph of crosswinds, yet most drag-resistant technologies improve aerodynamic performance for only a narrow subset of wind angles. Side cab fairings lose much of their effectiveness in crosswinds. The AeroWall closes that gap and improves stability and handling by reducing turbulence and its associated aerodynamic drag.
Crosswinds with AeroWall
The AeroWall works in all wind conditions, but its effectiveness is even more pronounced in crosswinds. The AeroWall creates a clean Aero-Line™ as the rig moves through the winds. The result is improved fuel efficiency along with fewer lane departures—making the road a safer place.