By 2050, the world’s population is expected to reach nine billion. As a result, urbanisation is increasing, and so too is the demand for personal mobility. Global energy demand is expected to double by 2050, and as more energy usage means more CO2 emissions, there is a need for new, clean energy. The best solution is to use existing energy in the most efficient way – so began Dr Selda Gunsel, Vice President of Shell Global Commercial Technology, at the inaugural Shell Lubricants Technology Lecture, held at Imperial College in London in late 2012.
Power generation accounts for one third of total emissions, and transport accounts for one fifth of total energy consumption, said Gunsel. Yet, while new and alternative vehicle powertrain technologies are exciting, two thirds of cars will still use internal combustion engines (ICEs) in 2050.
20% of the energy produced by an engine is lost through friction. For this reason, lubricants can play a key role in improving fuel efficiency and helping to reduce CO2 emissions. According to Gunsel, Shell has developed breakthrough engineering solutions like a split-lubrication system and low-viscosity synthetic lubricants. However, in order to bring these to market, “some of the existing industry specifications need to change. And all parts of the industry need to work together – we cannot bring it to market without partnerships”.
Joining Gunsel at the event were senior executives from suppliers and OEMs, who presented the case for co-development of lubricants and the need to change current industry specifications to enable the use of synthetic and low-viscosity lubricants that could play a role in improving engine efficiency and reducing CO2 emissions.
Here, we’ve collated thoughts from Dr. Selda Gunsel; Robert Plank, Vice President of Corporate Engineering, Schaeffler Technologies; Dave Salters, Head of Engine Development, Scuderia Ferrari; Mark Struglinski, Vice President of Infineum; and Professor Gordon Murray, on the growing importance of lubricants in the automotive industry.
Lubricants as a vehicle design parameter
Collaboration between Gordon Murray Design (GMD) and Shell Lubricants last year led to the development of an innovative concept engine lubricant in GMD’s T.25 city car capable of achieving a 6.5% improvement in fuel efficiency – a step up compared to the improvements of around 2.5% achieved in typical fuel economy lubricant development programmes.
Dr Selda Gunsel: We need to establish lubricants as a valuable design component, engineered with precision and blended with skill.
Professor Gordon Murray: Lubricants were something that typically got added after you’d finished the design of the car, and that’s about as bad as you can get from a philosophy point of view. So it made us think that we should apply the philosophy of working with people from the beginning on the design in future to incorporate every single thing, including things like fuels and lubricants. And hopefully the work we do with Shell in the future will go beyond powertrain and will look at every single component of the car which needs friction reduction.
We had to work very closely with Shell Lubricants’ engineers and scientists, in fact, on how lubricants could affect the engine of the T.25, because it’s a very low viscosity oil, and we had to follow some very strict rules in the early days until we got enough confidence to actually run the car in public. In the early days we were stepping gingerly, working very closely with Shell engineers, and we had to adopt different strategies for warming up and running the engine.
Robert Plank: We see two big areas where we can step forward together with lubricant suppliers. One is a basic area, when we compare and benchmark methods and simulation methods and just together make it more precise to predict the optimisation effects we have. For example, Shell can contribute to the lubricant simulation and the features of lubricant. We can bring in the surface and the features of the metal components, and bringing in both methods together we get a better prediction. The other thing that I have learned through the years is we have to regard the lubricant as a design parameter from the very beginning. It’s also valid for our components. So if we come together at the very beginning and take lubricants as a design parameter and bring surface or coating, for example, together then we can go into another area of optimisation.
Dr Selda Gunsel: The oil that we developed currently sits outside industry-accepted specifications. It’s an extremely low viscosity oil, 0W-10: these types of oil formulations may be used in racing applications but they are not commercial oils at this stage. The lowest viscosity you can find in the marketplace is the 0W-20 grade oil, so we need to ensure that these types of low viscosity oils can be commercialised in the marketplace but in order to do that, we have to show that these oils are durable, they provide the protection against wear just like the thicker oils. We need to show that these oils can provide protection that the engine manufacturers need. We need to change the specifications in order for these oils to be commercialised. We alone cannot make the specifications – it’s for the whole industry.
Now that we’ve shown that these oils work in a concept application, we are working with some major OEMs who are really interested in working in this space. We are currently running durability testing, which involves dynamo and lab testing as well as field trials. So far we are getting very good results in applications ranging from passenger cars to heavy duty truck applications. Durability, obviously, requires time so we need to run this for a number of years.
Professor Gordon Murray: For the first time ever, we can put a price on weight reduction: we put it at €5-€15 per kilogramme saved on the chassis. Once you’ve reduced the mass of the primary structure, you need smaller brakes, suspension, lighter steering, no power steering in some cases, lighter wheel components, lighter tyres – and so it goes on.
The trickle-down effect: applying F1 lubricants to mainstream vehicles
Dr Selda Gunsel: We work very closely with Ferrari Formula One, developing the base lubricants, engine oils, gear oils and fuels. This is a great research platform for us because there are no specifications: the only thing is to win. Whatever it takes we have a lot of flexibility in terms of lubricant formulation, gear oil formulation, and we design our fluids to operate under conditions that they would not normally be able to do – extreme temperatures, extreme roads, extreme speed. We work really closely and, as a result, we learn to push our products beyond their design specifications under the most extreme operating conditions; we take the learnings and bring them to our normal, everyday products.
Dave Salters: We are quite fortunate, because our objectives are very easy. We have to make the most powerful engines but with the same volume generally. Engine development was frozen for a while, but all that meant was that we moved on to something else to find an advantage. And the oil and the fuel weren’t frozen. The engine is incredibly efficient, so we do everything we can to minimise the losses in the engine. And we don’t really have any constraints. If we can come up with a good idea and it’s obtainable or not obtainable but we make it obtainable, we can follow that.
Seeking out the small, incremental gains in fuel efficiency
Dr Selda Gunsel: The advantage of lubricant technology is that it can successfully improve fuel efficiency and thereby help reduce tailgate emissions today, rather than waiting for a radical technological development in years to come.
Professor Gordon Murray: In terms of fuel economy gains, it feels like we have picked most of the low hanging fruit as far as engine design is confirmed. Now it’s time to focus on the small details that can make a big difference – and that includes lubricants. The work that Shell is doing in advanced lubricant engineering plays a really important role in enabling the kind of innovative and challenging design concepts we are developing at GMD to tackle emissions and fuel consumption.
Robert Plank: We deal with parts that nobody sees, like bearings. Tribology and lubricants is one of our core areas and is very important to us. If we look at the whole powertrain system, from the combustion engine through to the transmission to the wheels, there are a lot of components which are in motion. And if we talk about the mechanical losses within this system, there are three ways we can reduce those losses: firstly, reduce the forces; secondly, reduce the friction; and thirdly, avoid use by deactivation, power on demand, electrification or by downsizing. These are the three areas throughout the whole system where we can find places to take small steps to optimise.
Mark Struglinski : One of the biggest challenges is to develop an oil that keeps an engine factory-clean. Believe it or not, nobody has ever done this. It’s a really tough challenge. A clean engine lasts longer, so, in terms of sustainability you don’t have to either tear the engine down to rebuild it or replace it. Clean engines last longer, and have better emissions. They maintain their factory emissions properties through the life of the engine, so that produces a cleaner environment.
Without chemical additives, your lubricant won’t work. The things that you add to the oil to keep it clean also tend to make the fuel economy worse. So we had to find a way to balance those two, to keep the engine clean but also to deliver leading edge fuel economy. And it was a really difficult problem that needed some innovative approaches. We created a new friction modifier to do that. We used some chemistry that wouldn’t typically be used in these kinds of engine oils and we actually succeeded – it was launched last year into the marketplace.
Martin Kahl is the Editor of Greenstreetsoftware.info