DIGGING IN

Dispatches
of the most prominent of the futuristic
features is a Rankine waste heat recovery
system, mounted above the transmission
and in front of the battery box. That
achieves a 50% brake thermal efficiency,
which means half the energy in the fuel
actually makes it to a dyno.
Inside the cab, hotel loads are powered
using a solar panel incorporated into
the roof line, and a pair of belt-driven
alternators that capture kinetic energy as
a truck rolls down the road. “We trickle
charge the batteries when the truck is
driving,” Amar says. Together, they offer
14 hours of power for things like air
conditioning. And while the reshaped
roofline and solar panel eliminates the
skylight, the space inside the cab is now
lit with a virtual skylight that’s powered
with LEDs.
The truck’s shape itself is also decidedly
futuristic. “You don’t get 40% less drag
with just a few fairings,” Amar explained.
The truck builds around a traditional
VNL steel cab, but sits three inches taller
and moves forward eight inches, ensuring
a straighter flow of air up the front of the
truck. A wider back wall also creates a
the change that can be made without
sacrificing performance.
Meeting and exceeding targeted
weight savings (the original goal was
to be 40% lighter, but the SuperTruck
weighs 45% less) was made possible in
part with an aluminum frame that is 900
pounds lighter than its predecessor. The
weight savings were also realized despite
new technologies that were added to the
truck. About 4,700 pounds were removed,
but 1,500 pounds had to be added.
Still, there were some curves to
address along the way, and not simply in
the form of reshaped fairings.
“When a truck becomes this much
more efficient, this much more aerodynamic,
a lot of assumptions need
to be revisited,” he added. The idea of
capturing a truck’s kinetic energy, for
example, could be at odds with systems
like predictive cruise control that are also
designed for fuel economy. “Do you disengage
the driveline and coast, or do you
charge the batteries?”
Engineers have little time to rest in
the search for answers to questions like
that. Volvo is among manufacturers that
will also participate in the second phase
of the research known as SuperTruck
Drag is reduced 40% through aerodynamics.
Pascal Amar gives Dr. Ernest Moniz a tour of internal features. (Photo by John G. Smith)
wedge that directs air around the tractor
and to the back of the trailer. Meanwhile,
the trailer itself includes a boat tail, side
skirts, and reshaped front end.
By mounting the air conditioner’s condenser
at the back of the cab, engineers
were also able to introduce a smaller grill
at the front of the truck.
Other gains were realized by
“right- sizing” the engine, and opting
for a 425-horsepower D11. “You operate
the engine where it’s efficient, in
the sweet spot,” Amar says, referring to
“The interactions between the trailer
and tractor were much more complex
than we thought,” Amar says, referring
to how that led engineers to abandon
plans for a lower front bumper. Fuel cells
to power the hotel loads were replaced
with the system that uses solar panels
and captures kinetic energy. Plans for an
adjustable fifth wheel were abandoned
altogether because they simply wouldn’t
generate the expected returns. And while
carbon fiber was researched, it was left to
future projects.
II, leveraging US $20 million in federal
funds with the goal of doubling ton miles
per gallon when compared to the 2009
baseline, and creating a powertrain with
a brake thermal efficiency of 55%.
“We will make sure that this program
will be successful and we will bring more
value to our end users,” Nyberg says.
Partners in the project include
Michelin Americas Research Company
(tires), Wabash National (trailer),
Metalsa (lightweight frame), Johnson-
Matthey Inc. (exhaust aftertreatment
system catalysts), Oak Ridge National
Laboratory (exhaust aftertreatment
system testing / analysis), Peloton
Technology (connected vehicle/platooning),
Pennsylvania State University
(connected vehicle testing), Knight
Transportation (long-haul fleet), and
Wegmans Food Markets (regionalhaul
fleet).
“We have a lot of ideas we want to
throw at SuperTruck II,” said a clearly
excited Amar. “We generated so much
more innovation through the project. It
just keeps going.” TT
NOVEMBER 2016 17