2014-2020 Formula One 1.6l V6 turbo engine formula

[WhiteBlue]

....i'm assuming the teams are using the storing rate of ES as part of their efficiency excuse.
This i feel is behind the Mercedes aim of 40%, if you notice i'm relatively close with 38.92.

I'm not buying this theory. I think everybody is aware that you have a significant amount of regenerated kinetic energy for your lap energy budget. But it is not clouding the discussion of engine efficiency. Kinetic regeneration is fixed by the rules in it's performance. It is not a source of competitive advantage to the teams in terms of getting more power or energy from the engine they buy. So when the manufacturers speak about the performance criteria they need to focus on the ICE and the turbo design to demonstrate that they have an advantage. The definition of brake thermal efficiency for the ICE and for the ICE + turbo should be clear to the engineers involved in the development.

I will endulge a bit in speculation here. I do not believe that a company like Mercedes will make a dodgy claim that will make them look like a joke when it is found out to be fake. Until I get some evidence to the contrary I'm taking Marmorini's and Taffin's claim at face value. The Merc 40% has come without a name attached to it. So I would be more careful if it were not already supported by the Renault claim. Does anybody here have a doubt that Mercedes has the ability to match what Renault does in F1 engine development? I'm pretty sure the Merc board of directors is very seriously determined to have the best engine in F1 and will spare no effort or cost. In comparison with other manufacturers they have vast research resources in the field of engine development. I'm pretty sure Brixworth can ask for anything they want and they will get it. If Renault have 300 people working in Viry then Merc will have at least that kind of effort in Brixworth and Stuttgart combined.

[Holm86]

I would also think that given the same turbine, it does not necessarily follow that an increase in temperature before the turbine will lead to greater energy recover. It may just lead to hotter exhaust.

The idea is not to use the same turbine. The idea is if you have a higher temperature before the turbine there is a higher energy potential for the turbine. Then you would design that turbine to take advantage of that. Just like WB says above.

Note that increased temperatures in teh combustion chamber can be bad for the combustion processes.

I am aware of that. That's why direct injection is so important in raising the efficiency of an engine. Because you inject so late in the compression stroke.

[ringo]

....i'm assuming the teams are using the storing rate of ES as part of their efficiency excuse.
This i feel is behind the Mercedes aim of 40%, if you notice i'm relatively close with 38.92.

I'm not buying this theory. I think everybody is aware that you have a significant amount of regenerated kinetic energy for your lap energy budget. But it is not clouding the discussion of engine efficiency. Kinetic regeneration is fixed by the rules in it's performance. It is not a source of competitive advantage to the teams in terms of getting more power or energy from the engine they buy. So when the manufacturers speak about the performance criteria they need to focus on the ICE and the turbo design to demonstrate that they have an advantage. The definition of brake thermal efficiency for the ICE and for the ICE + turbo should be clear to the engineers involved in the development.

I will endulge a bit in speculation here. I do not believe that a company like Mercedes will make a dodgy claim that will make them look like a joke when it is found out to be fake. Until I get some evidence to the contrary I'm taking Marmorini's and Taffin's claim at face value. The Merc 40% has come without a name attached to it. So I would be more careful if it were not already supported by the Renault claim. Does anybody here have a doubt that Mercedes has the ability to match what Renault does in F1 engine development? I'm pretty sure the Merc board of directors is very seriously determined to have the best engine in F1 and will spare no effort or cost. In comparison with other manufacturers they have vast research resources in the field of engine development. I'm pretty sure Brixworth can ask for anything they want and they will get it. If Renault have 300 people working in Viry then Merc will have at least that kind of effort in Brixworth and Stuttgart combined.

White blue have you seen the words "brake thermal" being used by any of these teams when they say these figures?
until i see them use that, then the efficiency they quote will always be considered a dodgy value IMO.
As far as i'm concerned conversion efficiency is what i think they may be quoting, not brake thermal.

40% from the ICE alone is basically a diesel engine, unless they run stratified charge in a way, that is almost like dieseling the engine, at some arbitrary engine speed and power to prove a point, i don't think the ICE will see that kind of efficiency.
We can't sucumb to championing journalism over science. We can't bend science to conform to an agenda.
I just find it hard to buy something that doesn't seem at all to right.

As for renault they are also using this 40% as their efficiency figure. They simply cannot reinvent the otto cycle overnight, my brake thermal values are for ideal cycle so it infact neglects other losses that these teams will encounter during development, so in fact should have higher efficiency values.

As for renault's claim, it's not any more valid than Mercedes. Mercedes is probably more open as they put their number down in black and white. Renault's figure was quoted, but not published. Both teams claim 40%, but i feel they both know they are playing the same marketing game.
Conversion efficiency, which makes sense, is what these guys are quoting.

[pgfpro]

I wish they would just use the BSFC numbers instead of efficiency.

[Holm86]

Can anyone explain the logic of the raised crank height?? I know Scarbs talked about being able to fit larger clutches. But doesn't seems plausible to me. You would rather ad one more clutch plate than increase the diameter of them.

[ringo]

Can anyone explain the logic of the raised crank height?? I know Scarbs talked about being able to fit larger clutches. But doesn't seems plausible to me. You would rather ad one more clutch plate than increase the diameter of them.

Yes you have a point, the clutch is the least.
It may well be related to the KERS motor diameter, or the fact that the engine may need bigger bearings and structure to cope with the demands of having only 5 engines per season, and also the higher in cylinder forces experienced by the turbo v6 versus a v8.
There's considerable for more forces on the bearings.

[Holm86]

Can anyone explain the logic of the raised crank height?? I know Scarbs talked about being able to fit larger clutches. But doesn't seems plausible to me. You would rather ad one more clutch plate than increase the diameter of them.

Yes you have a point, the clutch is the least.
It may well be related to the KERS motor diameter, or the fact that the engine may need bigger bearings and structure to cope with the demands of having only 5 engines per season, and also the higher in cylinder forces experienced by the turbo v6 versus a v8.
There's considerable for more forces on the bearings.

I guess you could be right about the KERS motor. It should be larger next year with the effect doubled. But the output shaft of the KERS motor isn't coaxial with the crankshaft. There is a ratio between the two which allows you to lift the KERS motor if necessary. And the bearings shouldn't increase so much in diameter. More in width?

[WhiteBlue]

White blue have you seen the words "brake thermal" being used by any of these teams when they say these figures?
until i see them use that, then the efficiency they quote will always be considered a dodgy value IMO.
As far as i'm concerned conversion efficiency is what i think they may be quoting, not brake thermal.

40% from the ICE alone is basically a diesel engine, unless they run stratified charge in a way, that is almost like dieseling the engine, at some arbitrary engine speed and power to prove a point, i don't think the ICE will see that kind of efficiency.
We can't sucumb to championing journalism over science. We can't bend science to conform to an agenda.
I just find it hard to buy something that doesn't seem at all to right.

As for renault they are also using this 40% as their efficiency figure. They simply cannot reinvent the otto cycle overnight, my brake thermal values are for ideal cycle so it infact neglects other losses that these teams will encounter during development, so in fact should have higher efficiency values.

As for renault's claim, it's not any more valid than Mercedes. Mercedes is probably more open as they put their number down in black and white. Renault's figure was quoted, but not published. Both teams claim 40%, but i feel they both know they are playing the same marketing game.
Conversion efficiency, which makes sense, is what these guys are quoting.

You cannot expect them to use engineering and science language when they speak to a wider public. They would not be understood. I don't mind if you have different prediction at this time for the power we are going to see, but I keep my opinion. 38% BTE for the ICE and 41% BTE for the ICE + heat recovery at the crank. Anything they recover from kinetic will go on top. You can whip me when no power train reaches this target at the end of 2014. If they get higher I'll remind you and whip yours.

[chip engineer]

White blue have you seen the words "brake thermal" being used by any of these teams when they say these figures?
until i see them use that, then the efficiency they quote will always be considered a dodgy value IMO.
As far as i'm concerned conversion efficiency is what i think they may be quoting, not brake thermal.

40% from the ICE alone is basically a diesel engine, unless they run stratified charge in a way, that is almost like dieseling the engine, at some arbitrary engine speed and power to prove a point, i don't think the ICE will see that kind of efficiency.
We can't sucumb to championing journalism over science. We can't bend science to conform to an agenda.
I just find it hard to buy something that doesn't seem at all to right.

As for renault they are also using this 40% as their efficiency figure. They simply cannot reinvent the otto cycle overnight, my brake thermal values are for ideal cycle so it infact neglects other losses that these teams will encounter during development, so in fact should have higher efficiency values.

As for renault's claim, it's not any more valid than Mercedes. Mercedes is probably more open as they put their number down in black and white. Renault's figure was quoted, but not published. Both teams claim 40%, but i feel they both know they are playing the same marketing game.
Conversion efficiency, which makes sense, is what these guys are quoting.

You cannot expect them to use engineering and science language when they speak to a wider public. They would not be understood. I don't mind if you have different prediction at this time for the power we are going to see, but I keep my opinion. 38% BTE for the ICE and 41% BTE for the ICE + heat recovery at the crank. Anything they recover from kinetic will go on top. You can whip me when no power train reaches this target at the end of 2014. If they get higher I'll remind you and whip yours.

Maybe the Mercedes and Renault statements are quoting efficiency with LHV fuel energy if that is the European standard:

According to: http://en.wikipedia.org/wiki/Energy_con ... efficiency
"In Europe the usable energy content of fuel is typically calculated using the lower heating value (LHV) of that fuel, which definition assumes that the water vapor produced during fuel combustion (oxidation), remains gaseous, and is not condensed to liquid water so the latent heat of vaporization of that water is not usable. Using the LHV, a condensing boiler can achieve a "heating efficiency" in excess of 100% ( this does not violate the first law of thermodynamics as long as the LHV convention is understood, but does cause confusion). This is because the apparatus recovers part of the heat of vaporization, which is not included in the definition of the lower heating value of fuel. In the U.S. and elsewhere, the higher heating value (HHV) is used, which includes the latent heat for condensing the water vapor, and thus the thermodynamic maximum of 100% efficiency cannot be exceeded with HHV's use."

There is not a lot a difference for Diesel fuel: HHV=44.8, LHV=43.4, but for propane, the difference is substantial: HHV=50.35, LHV=46.35 MJ/kg. From: http://en.wikipedia.org/wiki/Higher_hea ... ting_value

The LHV seems more relevant to our discussion since there is likely no way for an F1 engine to use the additional energy in the HHV.

[ringo]

[
You cannot expect them to use engineering and science language when they speak to a wider public. They would not be understood. I don't mind if you have different prediction at this time for the power we are going to see, but I keep my opinion. 38% BTE for the ICE and 41% BTE for the ICE + heat recovery at the crank. Anything they recover from kinetic will go on top. You can whip me when no power train reaches this target at the end of 2014. If they get higher I'll remind you and whip yours.

So you're telling me 38% BTE for ICE alone corect?

I'm quoting you on that one.

Then you go on to say 41% with heat recovery.

Ok.
What i will say WB is that your type of efficiencies at this level of power density is highly unlikely. You can't have your cake and eat it. Toyota have atained 38% using valve timing to simulate the more efficient atkinson cycle. they also use exhaust gas regeneration. What suffers is the power output. These engines have very long strokes as well, the effective power stroke is much longer than the effective compression stroke by virtue of valve control. As far as i know this trickery is not permitted in F1.

Recently, Atkinson cycle has been used to describe a modified Otto cycle engine in which the intake valve is held open longer than normal to allow a reverse flow of intake air into the intake manifold. The effective compression ratio is reduced (for a time the air is escaping the cylinder freely rather than being compressed) but the expansion ratio is unchanged. This means the compression ratio is smaller than the expansion ratio. Heat gained from burning fuel increases the pressure, thereby forcing the piston to move, expanding the air volume beyond the volume when compression began. The goal of the modern Atkinson cycle is to allow the pressure in the combustion chamber at the end of the power stroke to be equal to atmospheric pressure; when this occurs, all the available energy has been obtained from the combustion process. For any given portion of air, the greater expansion ratio allows more energy to be converted from heat to useful mechanical energy meaning the engine is more efficient.

The disadvantage of the four-stroke Atkinson cycle engine versus the more common Otto cycle engine is reduced power density. Due to a smaller portion of the compression stroke being devoted to compressing the intake air, an Atkinson cycle engine does not take in as much air as would a similarly designed and sized Otto cycle engine.

Four-stroke engines of this type with this same type of intake valve motion but with a supercharger to make up for the loss of power density are known as Miller cycle engines.

While a modified Otto cycle engine using the Atkinson cycle provides good fuel economy, it is at the expense of a lower power-per-displacement as compared to a traditional four-stroke engine.[3] If demand for more power is intermittent, the power of the engine can be supplemented by an electric motor during times when more power is needed. This forms the basis of an Atkinson cycle-based hybrid electric drivetrain. These electric motors can be used independently of, or in combination with, the Atkinson cycle engine, to provide the most efficient means of producing the desired power. This drive train first entered production in late 1997 in the Japanese-market Toyota Prius.

Now these are pretty efficient if engineered well. Toyota gets 37% to 38%. So i'm really wondering how these typical otto cycle engines will compare to these atkinson cycle units. keep in mind, these aren't even brake thermal figures.

http://www.greencarcongress.com/2011/04 ... 10411.html

[WhiteBlue]

@ ringo, perhaps one should consider that very highly efficient, boosted otto racing engines of the current level were never designed before and certainly never before for a fuel flow limited formula. In 1987 people would have called you an idiot if you would have predicted that NA racing engines would rev up to 22.000 rpm one day. F1 engine engineers are very good to find new ways to create power. Turbo design, direct injection, combustion processes and staged working processes in general have not been researched for a long time in F1. I have identified nine areas of efficiency improvement in a previous post. I'm sure the engineers who are actually working in the field will find 20 and more fields of work where they will chip away at efficiency improvements.

All I'm doing is looking at ways how the communicated power and efficiency figures can be expressed in a coherent way.
The 38% BTE is very simply based on Marmorini's claim that the ICE alone will reach 650 bhp. The 41% BTE is based on my estimate that the MGU-H will take a peak load of 44.5 kW mechanical power from the turbine which gets reduced to 40 kW at the crank when it has passed various transformations. This figure is based on the 7% blow down recovery which has historically been achieved plus a bit more for small efficiency improvements that they will get from thermal optimizations. I have added 2.2% of the engine power in my estimate. So I now get excess turbine power of 9.2%. The biggest risk I see for my estimate is the 650 bhp assumption for the ICE. It can be lower like 610 or 630 bhp. But my impression is that Ferrari are a bit behind in the horses and that Merc and Renault will be coming out with more power in 2014. A spread of 50 bhp between new engines is not unusual, although in this case they are all to a very similar spec. So what? Sometimes one has to take a risk.

I could be totally wrong. Nobody can say honestly now that he knows what is going on in Brixworth, Viry and Maranello. But we can all have our personal opinion. I have been called a dreamer before when I have believed in 35% fuel reduction, a fuel flow well under 30 g/s and a race fuel budget of 100 kg. All those things have been rumoured well before they were eventually revealed by the regulations. I'm convinced we will see a similar process with power and BTE figures.

The objective of the regulators and the teams has been from day one to keept the current level of performance in F1 and that is not possible unless you essentially match the power output with much lower energy use. If you have 35% less fuel and an increase of 12% of BTE it makes some sense on close inspection. Keep in mind that you are shooting for the same power.

[Tommy Cookers]

I wish they would just use the BSFC numbers instead of efficiency.

the efficiency should have the advantage of not being influenced by some fuels having more MJ/kg or BTu/lb than others

but we don't all know whether in calculating efficiency from measured performance (bsfc) we should use UCV or LCV of the fuel
to me authors seem conveniently non-specific on this point
the only example I have found uses what I have to guess is a lower value, FWIW this seems to agree with Blanchimont's example
for our sort of fuel the difference is about 7% (the difference is just due to the Hydrogen content)
so if there was an engine that was 'really' 95% efficient based on the UCV it would be 102% efficient based on the LCV

Edit ..... my impression from old posts by edis is that the Honda SAE paper used for efficiency calcs 41.05 MJ
........ THIS IS LCV (of 84% Toluene 16% Heptane)
I haven't got the actual paper to check it

if chip engineers sources related to engines it seems that US and Europeans would have different efficiencies for the same engine
given that efficiency can only be 'measured' by calculation from measured performance (bsfc)

so seemingly the LCV is by convention the 'correct' value to use (although scientifically flawed)
if WBs 46 MJ is the LCV for 'his' fuel then it is already at what he suggests will be the limit of the possible or permissible

[dren]

Wikipedia has a chart of some BSFC numbers, or energy efficiency numbers. The Ford Ecoboost is around an efficiency of 33%. I'm expecting somewhere in the range of 35% for the ICE and 40% total for the power unit. This dictates a recovery of 14%, which seems rather high. Perhaps they are figuring some sort of energy % recovery from braking that is included in the 40%?

And like you're stating TC, it's hard to figure out because we don't know if the upper or lower value is to be used.

[Blanchimont]

And another point to consider is that the efficiency of an engine isn't constant at all. It varies with torque demand and rpm.
These high efficiency numbers usually are only valid for a narrow torque-rpm region. Therefore engines running at a constant rpm can manage to always stay at this sweet spot and achieve high efficiencies.

The lower the number ( g/kWh )in the picture is, the higher the efficiency is.

F1 engines are usually run at full throttle and high rpms which doesn't improve efficiency.

[WhiteBlue]

I'm inclined to assume that all power and efficiency figures that are published or talked about are for peak power. Nothing else makes sense considering that these cars are generally run for 60% and more in full power mode. I have never heard that a manufacturer quoted a power figure for safety car operation. Why should they suddenly start doing something like that?

Regarding the change of thermal power of the fuel I'm pessimistic that we will see significant changes. The current F1 fuel has to be optimized to the same requirements with regard to thermal content as the V6 fuel next years. No team can afford to loose lap time by carrying too much fuel mass. 10 kg difference gives you 0.4s/lap. Over a 55 lap race you will loose 22s to your next competitor. 10 kg compared to 160 kg typical start value are 6%. So even today a 6% difference will cost you a race or a championship. I have doubts that there is anything more than perhaps 1% optimization in the fuel specific heat. Hence I tend to simply use the values that have been used for two years on this board.