As far as aerodynamic add-on devices go, owner-operators may be positioned most advantageously — so says SmartTruck Systems’ Mitch Greenberg, who points to the fact that owner-operators many times run dedicated loads and/or routes, measure their fuel mileage more consistently and run the same equipment day in and day out.
Any differences that stem from aerodynamic add-on devices will more effectively and directly present themselves, Greenberg says, due to the aforementioned variables being so controlled, which is often not the case for large fleets looking to implement aero devices.Moreover, the industry as a whole is moving past skepticism of aero add-ons, Greenberg says, leaving owner-operators and fleets — instead of doubting — trying to find ones that work best for their operations.
SmartTruck is at its core a research company, founded in 2009 to study aerodynamic drag on tractor-trailers and how that drag can most effectively be eliminated. The company first unveiled its UnderTray systems in 2011 — devices the company says produce a more than 6 percent fuel savings, a number that has been reported by both customers and in the company’s own testing.
SmartTruck held a gathering of trucking industry press at its Greenville, S.C., headquarters this week to see its facility and check out the proving grounds where it gathers the information needed to develop and refine its products.
It also flexed its data-collecting muscle, showing off the vast amount of data it records and uses to test its products and detailing the years of rigorous research that went into designing, building and certifying its UnderTray systems.
Greenberg says the SmartTruck systems are completely contained within the already existing footprint of the trailer — a unique quality among trailer aero add-on devices. “This will result in a more durable, much more long-lasting product,” he said, allowing the undertray to last several trailer cycles and allow fleets to take it off an older trailer and put it on a new one.
Mike Henderson, chief scientist for SmartTruck and one of the company’s co-founders, said the data collection and testing methods were done in three basic legs: (1) computational fluid dynamics (CFD) testing, (2) coast-down testing and (3) SAE fuel mileage testing.
The CFD testing — a staple in the aviation industry, Henderson said — allowed the company to determine where the most drag occurred on a truck and trailer. The CFD testing pointed them to the mitigating the large pocket of low-pressure air directly behind the trailer as key to helping boost tractor-trailer aerodynamics and, subsequently, fuel economy.
The drag essentially creates a vacuum, sucking the truck back and causing the engine to make up for it, Greenberg says.
Next, SmartTruck used what Henderson called “the gold standard” in automotive aerodynamic testing — the coast down test — to test its product. The company has conducted more than 550 coast down tests at the Laurens Proving Grounds alone, in addition to weeks of testing at a 9-mile track in Pecos, Texas, and two weeks at Kennedy Space Center in Orlando.
The coast down test allows the company’s engineers to isolate the effects of drag caused by things like drivetrain and tires and to account for it at higher speed tests, where aerodynamic drag is greatest.
Lastly, to have the systems certified as fuel efficiency enhancing by EPA and stamped compliant for California Air Resources Board standards, it had to perform SAE testing. However, SAE testing is mostly outdated, Henderson said, though required by EPA. It will be replaced sometime next year with CFD testing, he said.
Henderson, whose background is in engineering in the aviation industry, said researching truck aerodynamics presented a unique opportunity, as there’s plenty of low-hanging fruit to tackle. “We’re not trying to find that last 2 percent [of gains],” he said. “We’re out looking for the first 70 [percent].”
SmartTruck offers three basic tiers of undertray systems: The UT1, the UT6 and the UT6-Plus.
The UT1 package consists of two components: the undertray and a roof fairing.
The UT6 is the undertray, roof fairing and a rear air deflector. The UT6-Plus includes everything in the UT6 package but also includes two side fairings on the rear of the trailer.