PROFESSOR POWER

Few people understand internal combustion engines like Professor Jamie Turner, so we ask him how manufacturers will get more power from them in the future, before looking at the tricks engine tuners use for those who simply can’t wait

The man who knows everything about engines

PROFESSOR OF ENGINES. NOW THAT’S A JOB title. Since 2015, Jamie Turner has been professor of engines and energy systems at Bath University. I’ve known Turner for years and first met him when he was at Lotus (he had two stints at the Norfolk company), where he worked on the Corvette ZR1 engine, Lotus’s own V8 and numerous skunkworks projects, including a test engine nicknamed Omnivore for its ability to run on virtually any fuel, and an optical engine that allowed the combustion process to be observed through a transparent cylinder. Turner worked for Cosworth F1 too, and prior to the Bath appointment led spark-ignition engine development at JLR.

Professor Turner also has a very cool office, most likely the coolest on campus. It is a shrine to the internal combustion engine and, to a lesser extent, Lotus. On a filing cabinet is a vast cylinder that’s one of the 18 that make a Bristol Centaurus radial aircraft engine. On a windowsill is a rotor and crankshaft from a rotary engine and also a sectioned Roots supercharger.

Yet while the man who helped develop Norton’s rotary engines (Turner adores bikes) loves a traditional motor, he’s not at all stuck in the past. Quite the opposite. ‘I drove a Tesla recently and really liked it,’ he admits, adding: ‘I felt a bit dirty.’

Fortunately, Turner predicts a long future for the internal combustion engine. ‘The reduction of carbon dioxide has been an absolute godsend to engineers,’ he explains. ‘The pursuit has made engineering incredibly important and has laid down fantastic challenges for us.’

In fact, while chatting with Turner about supercharging and amazing stuff such as the Napier Nomad flat-12 twostroke diesel compound aero engine (his favourite engine) is cool, the really fascinating area is his views on the future of the internal combustion engine and how we’re going to get more power from it.

‘One thing I think we’ll see fairly soon is the introduction of higher-octane fuels,’ he says. ‘Compared to what the car industry has achieved – about 30 per cent reduction in CO2 since 2000 – the oil industry hasn’t really played its part yet in reducing emissions. But it will do. They accept that higher-octane fuels will allow us to use higher compression ratios to improve combustion efficiency. From our side, I think the number-one move to allow higher compression ratios will be the development of water injection to reduce combustion temperatures – it’s all about controlling knock or pre-ignition. BMW has used water injection in the M4 GTS but that was a bit simple compared to the really optimised systems they have recently published on introducing the water with the fuel in direct injection.

‘Number two on my list of technologies that we’ll soon see more of is variable compression ratios. Nissan has produced a variable compression ratio engine but it’s not really a new idea at all. Neither is water injection, for that matter. There aren’t that many totally new ideas.’

So water injection and variable compression ratios are the two most important technologies in Turner’s view, but they’re top of a list that includes higher fuel pressures (350bar or more) and electric super- or turbocharging. ‘We’ll see more cars adopting 48-volt electrical systems to power these devices,’ says Turner, ‘and we’ll also see stopon-the-move coasting, in which the engine will stop and the clutch will disengage to reduce fuel consumption.’

A current Goodwin hobby horse is that modern engines are becoming soulless. The table-top torque spread and even the lack of turbo-lag have reduced much of the excitement that you get from revving an engine and feeling the power increase dramatically. Only the most exotic engines, such as Porsche’s naturally aspirated 4-litre

flat-six, Ferrari’s 6.3-litre V12 and also the Lamborghini Aventador’s V12 have old-school drama. So is the soulful engine dead?

‘That flat torque curve is there for emissions reasons, because it suits the drive-cycle used in testing,’ says Turner. ‘Also, it encourages drivers to change up a gear early and enables an automatic gearbox to do the same, both of which reduce emissions and fuel consumption.’

Professor Turner is in no doubt that as far as proper powertrains are concerned, plug-in hybrids will be a major trend. Which brings us neatly on to the more sexy matter of gas turbines as power generators. Jaguar fitted them to the C-X75 supercar concept of 2010, but the subject has since gone quiet.

‘For sure, they have a future,’ says Turner. ‘They’re efficient enough when running at a constant speed, but the important things are that they don’t need a cooling system and they’re light. Those are huge advantages for [electricity-generating] range-extenders because currently an internal combustion engine is used. For that you need separate cooling systems for the engine and the electrical system as they require cooling water at different temperatures, and you carry the engine at all times, even though you don’t really ever want to use it.’

Because Turner is on the side of academia, there is no corporate or company line to toe, meaning all subjects are open to discussion. Try talking about the possible rebirth of the two-stroke engine with an engineer from a car company and it’d be a short-run thing. The professor of engines doesn’t think the two-stroke is about to return, but he likes talking about it. And he’s still researching it now. ‘Thermodynamically they are just better. And thermodynamics is what it’s all about. You could say it’s a shame that we’ve spent 120 years building engines operating on the wrong cycle…’ ⌧

‘Gas turbines have a future: they don’t need a cooling system and they’re light’