7 ms·

Turbulent times for Formula 1 engines result in unprecedented efficiency gains

95 points by nkurz 10y ago

quahada 10y ago
Reminds me of this article from 2004 of one person making similar innovations as entire engineering teams with huge R&D budgets 12 years later. http://www.popsci.com/cars/article/2004-09/obsession-mr-singhs-search-holy-grail http://www.popsci.com/cars/article/2004-09/obsession-mr-sing...
- pmontra 10y ago
  Interesting. He has a website now http://www.somender-singh.com/ http://www.somender-singh.com/
aidenn0 10y ago
Any mention of the Prius using the Atkinson cycle brings out the inner pedant in me. I suppose to a certain degree, Toyota makes the engine, so they can call it what they want, but late intake valve closing is clearly quite distinct from the engine Atkinson invented (and indeed that design might not have achieved one goal of Atkinson's engine which was to circumvent the Otto cycle patent). Indeed, if there were any existing cycle for which it would make sense to name the Prius' engine after, it would be the Miller cycle, though that has always meant some sort of external compression of intake air (the original patent used a turbo, but all Miller cycle engine's I've ever seen have superchargers). One other interesting note is that the Miller cycle works best with a supercharger due to increased relative boost at low RPMs, where the drop in torque due to the late intake valve closing hurts the most. The Prius nicely sidesteps this by using an electric motor at low speeds.
- mrfusion 10y ago
  I'm not understanding the Atkinson cycle. It seems like less compression would be worse. What am I missing?
  - Gravityloss 10y ago
    There are limits to compression. The fuel-air mix will combust spontaneously if you compress it too much. So that's why max compression ratio is something like ten. So a normal engine has compression of ten and expansion of ten. A more efficient engine with a different cycle might still have compression of ten but expansion goes up to say eleven. This means it's possible to extract more power at the end of the power stroke. There are some tricks to achieve that. Toyota does it by creating an engine with a geometry that would otherwise have very high compression and expansion ratio, but they can avoid the high compression ratio: they don't close the intake valves when the cylinder has been sucked in full of fresh air, like in a normal engine. They keep them open so at the start of the compression cycle, fresh air flows backwards out of the cylinder for a while, before they close the valves.
    - ThenAsNow 10y ago
      Actually, the advantage of the Atkinson or Miller cycles is not due to avoiding autoignition limits. Rather it is because of, as you pointed out, the greater than unity ratio of (expansion ratio)/(compression ratio). So you are improving the ratio of work that can be extracted from the power cycle as compared to the work that you are doing on the mixture. For the same engine displacement as a standard Otto cycle engine, the maximum power you can develop with the Atkinson-type cycle is decreased, hence you trade efficiency for power density. The Miller cycle approach is a way to shift that balance back toward the Otto range by doing some precompression on the air.
  - aidenn0 10y ago
    Actually the compression stroke can only lose you energy. It's the power stroke that you want to be as long as possible for maximum efficiency. On top of this, there is an upper bound to the compression ratio for a given fuel-air mixture due to auto-ignition (basically if you compress a fuel-air mixture enough, it will ignite on its own). So by having the compression stroke shorter than the power stroke, you can harvest more energy at a given compression ratio.
- nradov 10y ago
  I recently ran across an interesting article about how Mazda has built two cars with Miller cycle engines. Only one was supercharged. http://jalopnik.com/5959547/forgotten-cars-the-mazda-millenia-and-mazdas-other-other-engine http://jalopnik.com/5959547/forgotten-cars-the-mazda-milleni...
  - aidenn0 10y ago
    Okay the Mazda 1.3L NA Miller cycle in the 2 is essentially the same cycle as the Prius. It probably won't have the best acceleration in the world, particularly at low RPMs. When the Prius came out, I remember several people saying you couldn't call it a Miller cycle due to it being NA. (Actually a few people said it needed a positive-displacement supercharger, until it was pointed out that the original Miller cycle patent was paired with a turbocharger).
revelation 10y ago
This is the sort of massively twisted world we end up with when externalities are not accounted for properly. Capitalism just spent in excess of 100 years and many trillions of hours to come up with hilariously convoluted designs still lagging massively behind the electric motor.
- trhway 10y ago
  >hilariously convoluted designs still lagging massively behind the electric motor. and where do electricity comes from? From a wall socket of extremely simple design, i guess... :) Even if one takes solar panels - the original energy of Sun fusion what comes to Earth is converted into electric energy with less than 30% efficiency at best and that is using the very new solar tech.
  - revelation 10y ago
    You can't pick an arbitrary start point. The "efficiency" of decomposed organic matter is going to be terrible but then just the energy used in the refinement of oil into a gallon of petrol can already get you further in an electric car than you could go in a petrol car.
    - street 10y ago
      Nope, not true. http://longtailpipe.com/ebooks/green-transportation-guide-buying-owning-charging-plug-in-vehicles-of-all-kinds/gasoline-electricity-and-the-energy-to-move-transportation-systems/the-6-kwh-electricity-to-refine-gasoline-would-drive-an-electric-car-the-same-distance-as-a-gasser/ http://longtailpipe.com/ebooks/green-transportation-guide-bu...
- largote 10y ago
  Good luck trying to make an electric car last 200+ miles at F1 race speeds. The technology for an electric F1 car just isn't there. Formula E is making advances in that regard but it's just nowhere near the level of F1 ATM.
maxxxxx 10y ago
It would be nice if Formula 1 would be a test bed for advanced technologies again like they did in the 90s with sequential automatic gearboxes.
Animats 10y ago
It's not yet clear if the added complexity will be worth it for ordinary cars, but it's interesting. 47% efficiency from an IC engine is impressive. Formula 1 is deliberately power-limited. But the Formula 1 technical rules [1] for the powerplant are all inputs, not outputs: Engine cubic capacity must be 1600cc. Crankshaft rotational speed must not exceed 15000rpm. Fuel mass flow must not exceed 100kg/h. So that's where the drive for higher efficiency comes from. [1] http://www.fia.com/file/40961/download/14591?token=5zH5vGzI http://www.fia.com/file/40961/download/14591?token=5zH5vGzI
- rurban 10y ago
  Exactly. F1 engines can easily turn up to 24.000 rpm, but are limited to 19.000rpm to help the smaller engine teams.
thenewwazoo 10y ago
I wish this article had more detail. Their description of the technology sounds a lot like stratified charge engines, which have been around for a long, long time... as in the Honda CVCC (the '70s forerunner to the Civic). Perhaps the difference is DI?
- ThenAsNow 10y ago
  It is very similar in the basics. A mixture that may be too lean to ignite via spark ignition can nonetheless sustain combustion if it is "hit" with enough ions, high-energy molecules, or radicals. Hence the "pre chamber" which initially ignites a richer mixture with a low ignition induction time. The difference between what is discussed here vs. the CVCC seems to be principally about the kind of precise control that we can achieve using today's technologies, including electronic control and micro-machining. From there, it looks like the shaping and direction of the combusted jet from the pre-chamber has been well-optimized in comparison to systems like CVCC.
MrFoof 10y ago
Another trick Formula 1 has had for a while, that will soon be seeing adoption into production cars, are camless engines. Valves are operated by electronically-controlled pneumatic actuators. This allows the valves to open and close faster, and makes intermediate states (in between fully closed and fully open) a lot easier. It's also a major reason as to why crank speeds are as high as they are in F1 cars, as they valves can be actuated fast enough to avoid the valve float that would otherwise occur in cammed engines with valve springs. Production cars currently tend to top out around 9450rpm (the 6.3L V12 in the LaFerrari), whereas Formula 1 cars have pushed close to 20,000rpm (though usually 16,000 - 18,000) for quite some time. Supercar manufacturer Koenigsegg is in the process of licensing their consumer version of the technology under the trade name "Freevalve". They've been developing it and testing it for an incredibly long time (I believe it's in its fourth or fifth generation), presumably to keep driving the costs down. I believe a few Chinese manufacturers are some of the initial companies signing on. It's around a 3-4% efficiency gain on its own. There's other fun stuff too, like Mercedes-Benz's split turbochargers. Basically, the turbine is located near the exhaust still, but a shaft runs through the engine to the other side to the compressor which is near the intakes -- less piping to get a cooled charge, less turbo lag (again, shorter piping), a more compact engine footprint, and needing smaller intake side pods than using normal turbochargers. Be interesting to see if those trickle down to consumer autos, whereas currently manufacturers are instead integrating 48V electrical systems for electric turbochargers (and more advanced lighting, hybrid functionality, etc.)
- gregpilling 10y ago
  Streetbikes have pushed 20,000 for quite a while, with steel valve springs. No pneumatic valve springs required https://en.wikipedia.org/wiki/Redline#Examples_of_motorcycle_engines https://en.wikipedia.org/wiki/Redline#Examples_of_motorcycle... Kawasaki ZXR 250: 19,000 rpm Honda CBR250RR: 19,000 rpm Yamaha FZR250: 18,500 rpm Yamaha YZF-R6: 16,200 rpm
  - MrFoof 10y ago
    Those are also far, far, far lower displacement. 19,000rpm, sure, but with 250cc displacement. In 1999, Formula 1 engine displacement was mandated to 2400cc and engine speeds were limited to 18,000 rpm to help keep costs in check -- they could still maintain 19,000rpm despite an order of magnitude higher engine displacement (and the far higher forces involved). Heck, remote control car nitromethane engines have operated in the 35000rpm - 40000 rpm range decades ago. But with minuscule displacements (~3cc). If valve springs worked at those speeds and 2000+ cc displacements, trust me, Formula 1 wouldn't have abandoned them several decades ago.
ksec 10y ago
Great! May be I am the only one in the nerd cicrle who dont want ICE cars to die and Electric cars to take over. I want, better and hugly more efficient engine along with cleaner fuel. In the comment section someone pointed out about vaporized fuel achieving much higher efficiency, why is that not being used?
venning 10y ago
The plasma jet injection thing sounds pretty novel, but I imagine a lot of the efficiency gain is tied up in the lean burn. The brake thermal efficiency gains of lean burn are well known, as are the reasons we don't use them in modern road cars. Burning so little fuel in so much air produces high levels of nitrogen oxides [1], bad for smog and acid rain and ozone. That's not a concern for an F1 car, but a serious issue for road cars that need to pass emissions tests since they can cause modern catalytic converters to stop functioning properly. See this note [2] on how unhelpful current NOx mitigation strategies have been. I believe the addition of three-way catalytic converters was partly responsible for the stagnant fleet fuel efficiency somewhere in the 1980s, since they had to make engines run richer than before to not foul the cats; though, we've since developed better converters. (Also, safety equipment and luxury things increasing weight affected fleet numbers.) [1] https://en.m.wikipedia.org/wiki/NOx https://en.m.wikipedia.org/wiki/NOx [2] https://en.m.wikipedia.org/wiki/NOx_adsorber#Market_use https://en.m.wikipedia.org/wiki/NOx_adsorber#Market_use
- venning 10y ago
  Following up, it looks like Mahle has actually been tying to address the NOx production. The OP links to this article [1] from 2010, which is mostly taken from three SAE papers that indicate they have been able to constrain the NOx in jet injection engines to "single digit ppm engine out NOx emissions" [2]. The EPA seems to indicate [3] that less than 1 ppm NOx post-catalytic converter is targeted. I don't know if their advancements allow for three-way catalytic converters on a lean burn engine, but that would be pretty impressive. [1] http://www.greencarcongress.com/2010/10/tji-20101027.html http://www.greencarcongress.com/2010/10/tji-20101027.html [2] http://papers.sae.org/2010-01-2196/ http://papers.sae.org/2010-01-2196/ [3, PDF] https://www3.epa.gov/ttncatc1/dir1/fnoxdoc.pdf https://www3.epa.gov/ttncatc1/dir1/fnoxdoc.pdf

95 points by nkurz 10y ago

Reminds me of this article from 2004 of one person making similar innovations as entire engineering teams with huge R&D budgets 12 years later. http://www.popsci.com/cars/article/2004-09/obsession-mr-singhs-search-holy-grail http://www.popsci.com/cars/article/2004-09/obsession-mr-sing...

pmontra 10y ago
Interesting. He has a website now http://www.somender-singh.com/ http://www.somender-singh.com/

aidenn0 10y ago

Any mention of the Prius using the Atkinson cycle brings out the inner pedant in me. I suppose to a certain degree, Toyota makes the engine, so they can call it what they want, but late intake valve closing is clearly quite distinct from the engine Atkinson invented (and indeed that design might not have achieved one goal of Atkinson's engine which was to circumvent the Otto cycle patent). Indeed, if there were any existing cycle for which it would make sense to name the Prius' engine after, it would be the Miller cycle, though that has always meant some sort of external compression of intake air (the original patent used a turbo, but all Miller cycle engine's I've ever seen have superchargers). One other interesting note is that the Miller cycle works best with a supercharger due to increased relative boost at low RPMs, where the drop in torque due to the late intake valve closing hurts the most. The Prius nicely sidesteps this by using an electric motor at low speeds.

mrfusion 10y ago
I'm not understanding the Atkinson cycle. It seems like less compression would be worse. What am I missing?
- Gravityloss 10y ago
  There are limits to compression. The fuel-air mix will combust spontaneously if you compress it too much. So that's why max compression ratio is something like ten. So a normal engine has compression of ten and expansion of ten. A more efficient engine with a different cycle might still have compression of ten but expansion goes up to say eleven. This means it's possible to extract more power at the end of the power stroke. There are some tricks to achieve that. Toyota does it by creating an engine with a geometry that would otherwise have very high compression and expansion ratio, but they can avoid the high compression ratio: they don't close the intake valves when the cylinder has been sucked in full of fresh air, like in a normal engine. They keep them open so at the start of the compression cycle, fresh air flows backwards out of the cylinder for a while, before they close the valves.
  - ThenAsNow 10y ago
    Actually, the advantage of the Atkinson or Miller cycles is not due to avoiding autoignition limits. Rather it is because of, as you pointed out, the greater than unity ratio of (expansion ratio)/(compression ratio). So you are improving the ratio of work that can be extracted from the power cycle as compared to the work that you are doing on the mixture. For the same engine displacement as a standard Otto cycle engine, the maximum power you can develop with the Atkinson-type cycle is decreased, hence you trade efficiency for power density. The Miller cycle approach is a way to shift that balance back toward the Otto range by doing some precompression on the air.
- aidenn0 10y ago
  Actually the compression stroke can only lose you energy. It's the power stroke that you want to be as long as possible for maximum efficiency. On top of this, there is an upper bound to the compression ratio for a given fuel-air mixture due to auto-ignition (basically if you compress a fuel-air mixture enough, it will ignite on its own). So by having the compression stroke shorter than the power stroke, you can harvest more energy at a given compression ratio.
nradov 10y ago
I recently ran across an interesting article about how Mazda has built two cars with Miller cycle engines. Only one was supercharged. http://jalopnik.com/5959547/forgotten-cars-the-mazda-millenia-and-mazdas-other-other-engine http://jalopnik.com/5959547/forgotten-cars-the-mazda-milleni...
- aidenn0 10y ago
  Okay the Mazda 1.3L NA Miller cycle in the 2 is essentially the same cycle as the Prius. It probably won't have the best acceleration in the world, particularly at low RPMs. When the Prius came out, I remember several people saying you couldn't call it a Miller cycle due to it being NA. (Actually a few people said it needed a positive-displacement supercharger, until it was pointed out that the original Miller cycle patent was paired with a turbocharger).

revelation 10y ago

This is the sort of massively twisted world we end up with when externalities are not accounted for properly. Capitalism just spent in excess of 100 years and many trillions of hours to come up with hilariously convoluted designs still lagging massively behind the electric motor.

trhway 10y ago
>hilariously convoluted designs still lagging massively behind the electric motor. and where do electricity comes from? From a wall socket of extremely simple design, i guess... :) Even if one takes solar panels - the original energy of Sun fusion what comes to Earth is converted into electric energy with less than 30% efficiency at best and that is using the very new solar tech.
- revelation 10y ago
  You can't pick an arbitrary start point. The "efficiency" of decomposed organic matter is going to be terrible but then just the energy used in the refinement of oil into a gallon of petrol can already get you further in an electric car than you could go in a petrol car.
  - street 10y ago
    Nope, not true. http://longtailpipe.com/ebooks/green-transportation-guide-buying-owning-charging-plug-in-vehicles-of-all-kinds/gasoline-electricity-and-the-energy-to-move-transportation-systems/the-6-kwh-electricity-to-refine-gasoline-would-drive-an-electric-car-the-same-distance-as-a-gasser/ http://longtailpipe.com/ebooks/green-transportation-guide-bu...
largote 10y ago
Good luck trying to make an electric car last 200+ miles at F1 race speeds. The technology for an electric F1 car just isn't there. Formula E is making advances in that regard but it's just nowhere near the level of F1 ATM.

maxxxxx 10y ago

It would be nice if Formula 1 would be a test bed for advanced technologies again like they did in the 90s with sequential automatic gearboxes.

Animats 10y ago

It's not yet clear if the added complexity will be worth it for ordinary cars, but it's interesting. 47% efficiency from an IC engine is impressive. Formula 1 is deliberately power-limited. But the Formula 1 technical rules [1] for the powerplant are all inputs, not outputs: Engine cubic capacity must be 1600cc. Crankshaft rotational speed must not exceed 15000rpm. Fuel mass flow must not exceed 100kg/h. So that's where the drive for higher efficiency comes from. [1] http://www.fia.com/file/40961/download/14591?token=5zH5vGzI http://www.fia.com/file/40961/download/14591?token=5zH5vGzI

rurban 10y ago
Exactly. F1 engines can easily turn up to 24.000 rpm, but are limited to 19.000rpm to help the smaller engine teams.

thenewwazoo 10y ago

I wish this article had more detail. Their description of the technology sounds a lot like stratified charge engines, which have been around for a long, long time... as in the Honda CVCC (the '70s forerunner to the Civic). Perhaps the difference is DI?

ThenAsNow 10y ago
It is very similar in the basics. A mixture that may be too lean to ignite via spark ignition can nonetheless sustain combustion if it is "hit" with enough ions, high-energy molecules, or radicals. Hence the "pre chamber" which initially ignites a richer mixture with a low ignition induction time. The difference between what is discussed here vs. the CVCC seems to be principally about the kind of precise control that we can achieve using today's technologies, including electronic control and micro-machining. From there, it looks like the shaping and direction of the combusted jet from the pre-chamber has been well-optimized in comparison to systems like CVCC.

MrFoof 10y ago

Another trick Formula 1 has had for a while, that will soon be seeing adoption into production cars, are camless engines. Valves are operated by electronically-controlled pneumatic actuators. This allows the valves to open and close faster, and makes intermediate states (in between fully closed and fully open) a lot easier. It's also a major reason as to why crank speeds are as high as they are in F1 cars, as they valves can be actuated fast enough to avoid the valve float that would otherwise occur in cammed engines with valve springs. Production cars currently tend to top out around 9450rpm (the 6.3L V12 in the LaFerrari), whereas Formula 1 cars have pushed close to 20,000rpm (though usually 16,000 - 18,000) for quite some time. Supercar manufacturer Koenigsegg is in the process of licensing their consumer version of the technology under the trade name "Freevalve". They've been developing it and testing it for an incredibly long time (I believe it's in its fourth or fifth generation), presumably to keep driving the costs down. I believe a few Chinese manufacturers are some of the initial companies signing on. It's around a 3-4% efficiency gain on its own. There's other fun stuff too, like Mercedes-Benz's split turbochargers. Basically, the turbine is located near the exhaust still, but a shaft runs through the engine to the other side to the compressor which is near the intakes -- less piping to get a cooled charge, less turbo lag (again, shorter piping), a more compact engine footprint, and needing smaller intake side pods than using normal turbochargers. Be interesting to see if those trickle down to consumer autos, whereas currently manufacturers are instead integrating 48V electrical systems for electric turbochargers (and more advanced lighting, hybrid functionality, etc.)

gregpilling 10y ago
Streetbikes have pushed 20,000 for quite a while, with steel valve springs. No pneumatic valve springs required https://en.wikipedia.org/wiki/Redline#Examples_of_motorcycle_engines https://en.wikipedia.org/wiki/Redline#Examples_of_motorcycle... Kawasaki ZXR 250: 19,000 rpm Honda CBR250RR: 19,000 rpm Yamaha FZR250: 18,500 rpm Yamaha YZF-R6: 16,200 rpm
- MrFoof 10y ago
  Those are also far, far, far lower displacement. 19,000rpm, sure, but with 250cc displacement. In 1999, Formula 1 engine displacement was mandated to 2400cc and engine speeds were limited to 18,000 rpm to help keep costs in check -- they could still maintain 19,000rpm despite an order of magnitude higher engine displacement (and the far higher forces involved). Heck, remote control car nitromethane engines have operated in the 35000rpm - 40000 rpm range decades ago. But with minuscule displacements (~3cc). If valve springs worked at those speeds and 2000+ cc displacements, trust me, Formula 1 wouldn't have abandoned them several decades ago.

ksec 10y ago

Great! May be I am the only one in the nerd cicrle who dont want ICE cars to die and Electric cars to take over. I want, better and hugly more efficient engine along with cleaner fuel. In the comment section someone pointed out about vaporized fuel achieving much higher efficiency, why is that not being used?

venning 10y ago

The plasma jet injection thing sounds pretty novel, but I imagine a lot of the efficiency gain is tied up in the lean burn. The brake thermal efficiency gains of lean burn are well known, as are the reasons we don't use them in modern road cars. Burning so little fuel in so much air produces high levels of nitrogen oxides [1], bad for smog and acid rain and ozone. That's not a concern for an F1 car, but a serious issue for road cars that need to pass emissions tests since they can cause modern catalytic converters to stop functioning properly. See this note [2] on how unhelpful current NOx mitigation strategies have been. I believe the addition of three-way catalytic converters was partly responsible for the stagnant fleet fuel efficiency somewhere in the 1980s, since they had to make engines run richer than before to not foul the cats; though, we've since developed better converters. (Also, safety equipment and luxury things increasing weight affected fleet numbers.) [1] https://en.m.wikipedia.org/wiki/NOx https://en.m.wikipedia.org/wiki/NOx [2] https://en.m.wikipedia.org/wiki/NOx_adsorber#Market_use https://en.m.wikipedia.org/wiki/NOx_adsorber#Market_use

venning 10y ago
Following up, it looks like Mahle has actually been tying to address the NOx production. The OP links to this article [1] from 2010, which is mostly taken from three SAE papers that indicate they have been able to constrain the NOx in jet injection engines to "single digit ppm engine out NOx emissions" [2]. The EPA seems to indicate [3] that less than 1 ppm NOx post-catalytic converter is targeted. I don't know if their advancements allow for three-way catalytic converters on a lean burn engine, but that would be pretty impressive. [1] http://www.greencarcongress.com/2010/10/tji-20101027.html http://www.greencarcongress.com/2010/10/tji-20101027.html [2] http://papers.sae.org/2010-01-2196/ http://papers.sae.org/2010-01-2196/ [3, PDF] https://www3.epa.gov/ttncatc1/dir1/fnoxdoc.pdf https://www3.epa.gov/ttncatc1/dir1/fnoxdoc.pdf