Improving aerodynamics can enable a truck and trailer combination to slide through the air rather than hit it head-on. Brenton O’Connor drives Volvo’s latest super-slippery FH – Images by Torque it Up Photography.
Someone once said to me, when it comes to operating efficiently in the transport game, it’s not what you make, but what you save. Obviously in many cases, if the transport company puts up its price, whether that is per tonne, per pallet or per load, they are likely to be undercut by a competitor, so the real option to increase profitability is to reduce inputs (costs).
The largest of those costs for many transport companies, after wages, is fuel. For those fleets doing high kilometres in interstate line haul averaging between 200,000 and 300,000 km per year, fuel is a massive input. Every 0.1 additional kilometres gained from each litre of diesel has genuine effects on their bottom line.
It was with this philosophy that Volvo Australia has launched its Fuel Super Truck, which is a truck and B-double curtainsider combination with a number of key modifications designed to achieve one thing – reduce fuel consumption.
As Clive Jones, vice president of sales for Volvo Trucks Australia, explained, “The Volvo Fuel Super Truck is more than just a concept. It is a real-world truck specially engineered for Australian conditions with a fuel-efficiency-optimised driveline and streamlined aerodynamics”.
PowerTorque recently had the opportunity to spend a day travelling from CMV’s impressive new Derrimut facility through to Volvo’s own company store in Blacktown Sydney, via the Hume highway. Accompanying me for this journey was Volvo Group Australia’s recently appointed fuel efficiency manager, Matt Wood. Matt, an industry veteran both operating trucks and also as a transport journalist, spearheaded this project to see what was possible when a truck is specified correctly, drag is reduced significantly, and also when correct driver training practices are in place.
These changes are all geared towards the operator so that each litre of fuel can be exploited to provide the maximum kilometres per litre. The full suite of innovations this truck demonstrated are all aimed with three key considerations – a reduction in fuel economy, increased safety for the driver and other road users, and, thirdly, making the operator’s job all that much easier on a day-to=day basis.
Upon an initial walk around of the vehicle, Matt is quick to explain the truck shown is nothing new or nothing that is not available for Volvo customers to order today. What the vehicle demonstrates is a unique suite of specifications that are available today, combined with the primary focus of gaining extra kilometres per litre of fuel. Matt explains that this truck is 20 percent more fuel efficient than the baseline standard spec Volvo FH16 against which this truck was benchmarked. No mean feat, given the baseline FH16 is already regarded as an industry leader in terms of fuel economy.
The truck provided as part of our test was a Volvo FH16 with Globetrotter cabin, which had been derated to 540 hp, rather than 600 hp or 700 hp typically found in FH16s.
Whereas 540 hp Volvo FHs are typically powered by the 13-litre engine at maximum output, for the purposes of this evaluation the 16-litre variant was selected due to its extra torque at low rpm. This allowed Volvo to gear the truck with a 3.01:1 rear axle ratio to provide a 100 km/h top speed with a mere 1260 rpm.
Volvo has been able to spec the truck this way through the recent addition of crawler gears to the I-Shift transmission. In this instance, a single crawler gear was added to the Volvo I-Shift transmission to provide the start-ability required, which would not otherwise be available with such a tall rear-axle ratio. The other benefit of the crawler gear is a very slow low reverse gear, which will alleviate the many concerns of Australian operators where European transmissions that have a reverse gear ratio that moves too fast at idle speeds when reversing B-doubles and long truck and dog combinations in tight areas.
In addition to the low gearing and tall rear axle ratio, Volvo has undertaken many other fuel-efficiency measures, including removing the front sun visor to help reduce drag, and adding a front apron underneath the front bumper to help reduce turbulence and drag under the combination. A locally sourced additional aero kit was installed to close up the gap between the rear of the cabin and the front of the A-trailer, and additional fairings were mounted on the fuel tanks and also the front step box, again, all to reduce drag.
A big change made by Volvo has been the tyres selected, which included super-singles for the entire combination including the drive axles of the truck to reduce drag and rolling resistance. On the steer axle were 385/55 R22.5 Michelin X Line Energy F tyres with a unique lip on the outer casing of the tyre designed to reduce spray. On the drive were 445/50 R22.5 One Line Energy D tyres that are a wide single drive tyre, while the trailers were sporting Michelin X 385/55R22.5 X Line Energy T low rolling-resistance tyres.
When it comes to the trailers, The MaxiTRANS curtainsiders underwent significant modifications including the fitment of wide single tyres, full fairings under the bodies of both A and B-trailers and also fairings around the wheel area with struts added so they can be raised in order to change tyres as required. Furthermore, there were extra fairings added between the A and B-trailer also to help reduce wind resistance.
At a time when basically the whole of NSW is classified as being in severe drought, the weather on the day of the trial from Melbourne through to Sydney was appalling. Undoubtedly, the fuel figures achieved would have been severely affected by these conditions, which included both gale force winds and also heavy rain. Wet roads have a severe impact on fuel economy as they create drag, with the truck having to push through and dissipate road surface water.
My initial personal viewpoint was that this B-double combination would be severely lacking in overall ability due to the extremely tall rear axle ratios. However, Matt assured me it was still a good drive, as the truck is geared to sit at 1260 rpm at 100 km/h, slap bang in the middle of the maximum torque on this engine, which is 2650 Nm from 1000 tob1450 rpm. Additionally, to help promote fuel-efficient driving, both manual mode and the kickdown function were disabled so that the truck made all decisions regarding gearshift points and peak engine rpm.
Surprisingly, the combination, at a gross weight of 63 tonnes, performed extremely well and I was not left feeling shortchanged when it came to performance. Despite the aforementioned wind and rain, the truck maintained an average speed of 89 km/h, with only a few of the climbs on the Hume bringing the speed back to below 40 km/h. For the route, an overall average of 49.50 litres per 100 km (2.020 km/l) was recorded, which, given the gale winds and heavy rains, was extremely good.
Matt’s advice in the pursuit of fuel economy included using the cruise control as much as possible. Contributing to this reasoning was the Volvo iSee technology, where the truck maps the road network and will communicate with other Volvo trucks on the road in order for the truck to ‘learn the road’ before travelling over it personally. This can achieve real gains when the truck knows it is three quarters of the way up the hill and able to back off the power through already ‘knowing’ it can roll over the top of the hill and regain speed on the downhill side. Additionally, the iRoll feature is working constantly whenever possible, with the transmission automatically selecting neutral when there are no throttle or engine/service-brake inputs, aiming to help stretch every litre of diesel to cover as many kilometres as possible.
As with any Volvo, driver comfort and safety was top rate. Seat travel for taller drivers isn’t as good as the Scania, as the seat fowls against the bunk when slid right back. Personally, I didn’t find the driver’s seat as comfortable as some of its competitors, particularly the one fitted to the new Mercedes Actros.
The visibility out of the FH cabin is exceptional with the low-cut windows in the doors, allowing an excellent panoramic view of the surrounds. The revised mirrors fitted to the FH are both designed to be more wind efficient and also to help to reduce blind spots, which was a common complaint on the old model truck.
Obviously, this specific build for Volvo will not suit every application. Due to Australia’s tyre regulations, the wide singles on the trailer and drive axles reduce the permissible gross weight allowed on the combination. Other aspects of the aerodynamic aids, such as the low skirts on both the prime mover and the trailer, will severely restrict the accessibility into any off-road terrain. It’s also a point of concern where animal strikes are the norm. However, the point of the exercise is to demonstrate to Australian operators that in today’s trucking it’s necessary to consider options, and that by selecting the right combination of driveline components they can gain further kilometres per litre. As mentioned earlier, it’s better to consider the whole of life costs and what the operator can save, as this will have tangible effects on their bottom line.