2014-2020 Formula One 1.6l V6 turbo engine formula

[wuzak]

They have valves for brake balance, power steering which are activated by electricity.

I believe electric power steering is banned.

Not sure if they use electrics for brake balance adjustment now, but they certainly will next year (for allowed brake balance compensation). Also, not sure if they use valves for adjusting brake balance.

[wuzak]

• Seventh your thermal efficiency improves by increasing engine and exhaust temperatures.

This is incorrect.

Thermal (Carnot) efficiency is defined as = (T1 - T2)/T1

Where
T1 is the temperature of the source (ie the combustion chamber) and
T2 is the temperature of the sink (ie exhaust)

Temperatures in Kelvin or Rankine.

So, lets say we have a combustion temperature of 1000K and exhaust of 650K. The efficiency is = (1000 - 650)/1000 = 35%

If we raise the exhaust temperature 100K we now get = (1000 - 750)/1000 = 25%.

If we increase the engine temperatures by the same as the exhaust temperatures we get:
= (1100 - 750)/1100 = 32%

Logically, if you have the same combustion temperatures and lower the exhaust temperatures you have extracted more energy from the combustion gases.

eg
= (1000 - 550)/1000 = 45%

Now, if you want to raise both the engine and exhaust temperatures to gain efficiency, the engine temperatures have to be raised more.

So, in my example, if we move the exhaust temperature up by 100K to 750K we have to raise the engine temperatures by at least 153.6K to get a gain in efficiency.

To get it up to 40% with a 100K exhaust temperature increase would require a 249.6K increase in engine temperatures.

[wuzak]

IMO quite different, for high UCV/kg and high detonation resistance (Octane number)
the rules seem to call for 87 Octane, but I can't understand whether this is max or min
this is the mean RON+MON, these are very low rpm lean mixture tests
the traditional trick is to use fuel which passes these tests but has higher detonation resistance at rich mixture (Toluene etc)
but for the first time ever they won't be using rich mixture

Shell have said that current fuel can be blended (presumably after combustion speed?) for max CV/litre, or differently for max CV/kg
(and that Octane number eg is unimportant at current rpm. Honda in an SAE paper 50 years ago said their 18000 rpm 125 cc motorcycles worked just as well with 73 Octane fuel)

The octane level is maximum.

[wuzak]

Further to the reasons why F1 engines can be/are more efficient than road car engines, and possibly the key, is that they are designed to run in a relatively narrow performance band.

They don't have to do both rapid acceleration (relatively speaking) and cruise along the highway barely above idle.

F1 engines also spend far more of their time with the throttle wide open, and very small amount of time with it fully closed.

[WhiteBlue]

• Seventh your thermal efficiency improves by increasing engine and exhaust temperatures.

This is incorrect.

Thermal (Carnot) efficiency is defined as = (T1 - T2)/T1

Where
T1 is the temperature of the source (ie the combustion chamber) and
T2 is the temperature of the sink (ie exhaust)

Temperatures in Kelvin or Rankine.

So, lets say we have a combustion temperature of 1000K and exhaust of 650K. The efficiency is = (1000 - 650)/1000 = 35%

If we raise the exhaust temperature 100K we now get = (1000 - 750)/1000 = 25%.

If we increase the engine temperatures by the same as the exhaust temperatures we get:
= (1100 - 750)/1100 = 32%

Logically, if you have the same combustion temperatures and lower the exhaust temperatures you have extracted more energy from the combustion gases.

eg
= (1000 - 550)/1000 = 45%

Now, if you want to raise both the engine and exhaust temperatures to gain efficiency, the engine temperatures have to be raised more.

So, in my example, if we move the exhaust temperature up by 100K to 750K we have to raise the engine temperatures by at least 153.6K to get a gain in efficiency.

To get it up to 40% with a 100K exhaust temperature increase would require a 249.6K increase in engine temperatures.

We know that thre will be an effort to reduce the cooling by running both higher engine and exhaust temperatures. This will lead to higher heat regeneration. Perhaps it will only be a small contribution but many small bits can make up an elephant.

[Blackout]

http://www.honda.com/newsandviews/artic ... id=7315-en

[WhiteBlue]

It was expected that Honda would continue Le Mans and so the Honda/Magneti Marelli/Wirth package for 2015 is not a big surprise. Honda can collect some valuable experience in another fuel flow regulated racing class ahead of the 2015 F1 program with the engine and the chassis in 2014. But there are obvious differences to F1. The 2.2 L engine will have lower boost than a 1.6L V6 and the thermal stressing of a 5000+ km endurance run will be different to five or six F1 weekends in variable climatic conditions. The energy recovery will also be very different. I expect the LMP series engines to run without electric compounding. But that remains to be seen. Thanks for the update Blackout.

[wuzak]

We know that thre will be an effort to reduce the cooling by running both higher engine and exhaust temperatures. This will lead to higher heat regeneration. Perhaps it will only be a small contribution but many small bits can make up an elephant.

The effort to raise coolant temperatures is to minimise the size of the radiators and help the aerodynamicists, since there will be a lot of coolers for them to deal with.

It doesn't necessarily follow that the increased temperatures will lead to improved efficiency and/or greater recovery.

They are also endeavouring to enable the oil to run at higher temperatures. This is because what is not going out the coolant has to leave somewhere.

[WhiteBlue]

We know that thre will be an effort to reduce the cooling by running both higher engine and exhaust temperatures. This will lead to higher heat regeneration. Perhaps it will only be a small contribution but many small bits can make up an elephant.

The effort to raise coolant temperatures is to minimise the size of the radiators and help the aerodynamicists, since there will be a lot of coolers for them to deal with.

It doesn't necessarily follow that the increased temperatures will lead to improved efficiency and/or greater recovery.

They are also endeavouring to enable the oil to run at higher temperatures. This is because what is not going out the coolant has to leave somewhere.

I do not understand your logic here. If the heat rejection is to be reduced more energy is available for conversion into power. It isn't very relevant where exactly this conversion takes place, in the ICE or in the turbine. The important point is that the increased temperatures will lead to a higher extraction potential that can ultimately be exploited by the waste heat recovery system.

[Tommy Cookers]

.......... exploited by the waste heat recovery system.

there is no waste heat recovery system in 2014 F1
despite the impression that you (and the FIA) are again trying to cultivate
the French have been spraying around the buzzword 'thermal' for over 50 years, eg for their special interest at Le Mans
they love to do this, it means nothing

the turbine recovers waste kinetic energy or waste pressure energy
as is shown by the energy recovery balance for the Wright T-C Fig 15 in the reference that I gave
a week ago you seemed to accept this

waste heat can only be recovered by eg adding the Rankine ('steam') cycle or the Stirling ('air') cycle
BMW seem (contrary to the impression you choose to give) to have done substantial 'Turbosteamer' work since 2006
now recovering from both exhaust and coolant heat

the waste heat in an SI engine exhaust is usually as large as the entire engine output power (car diesels similarly with coolant)
if turbines actually recovered this engines would long ago have in this way become conspicuously efficient
rather than still being conspicuously inefficient

[WhiteBlue]

.......... exploited by the waste heat recovery system.

there is no waste heat recovery system in 2014 F1
despite the impression that you (and the FIA) are again trying to cultivate
the French have been spraying around the buzzword 'thermal' for over 50 years, eg for their special interest at Le Mans
they love to do this, it means nothing

the turbine recovers waste kinetic energy or waste pressure energy
as is shown by the energy recovery balance for the Wright T-C Fig 15 in the reference that I gave
a week ago you seemed to accept this

waste heat can only be recovered by combining eg adding the Rankine ('steam') cycle or the Stirling cycle
BMW seem (contrary to the impression you choose to give) to have done substantial 'Turbosteamer' work since 2006
now recovering from both exhaust and coolant heat
perhaps you should tell them they are wrong

the waste heat in an SI engine is usually as large as the entire engine output power
if turbines actually recovered this engines would long ago have in this way become conspicuously efficient
rather than still being conspicuously inefficient

I'm afraid you are not correct with this view. The turbine of the turbo charger is a waste heat energy recovery device in addition to it's function to recover kinetic energy. This follows from the simple observation that every turbine has a pressure drop and that adiabatic or near adiabatic expansion produces a decrease of the gas temperature. You are surely aware of that fundamental effect which we also see during the compression with different direction. The gas (air) gets considerably heated up and stores heat energy in the process. Amontons' Law of Pressure-Temperature P1*T2=P2*T1 is describing that physical phenomenon btw. http://en.wikipedia.org/wiki/Gay-Lussac ... rature_law
In order for a turbine to reduce the gas temperature it must take out energy from the gas that represents the specific heat capacity of the gas times the temperature difference. You can also describe it as the potential energy stored in the gas when you decompress it by a pressure differential or the work extracted by the mass flow over a pressure differential. The main take away from the physics review is that indeed heat energy is recovered by the turbine. If the exhaust gas enters the turbine at a higher temperature more energy can be extracted by the turbine.

An exhaust gas turbine will only work to a certain level of enthalpy or energy content in the exhaust gas. If the temperature and pressure become too low you have to use other means of waste heat recovery like the Rankine process you mentioned. The Rankine process is not fundamentally different to the primary heat extraction. It also uses a turbine and a working fluid. The difference is that the process uses condensation/evaporation of a working fluid in a secondary fluid circuit. The fluid undergoes phase changes at low temperature. The latent energy of the phase change is exploited to transfer heat energy from the primary medium to the secondary fluid in an isobaric heat exchanger. Hence low level heat energy can be extracted from the first medium (the exhaust gas).
Both the turbine expansion and the Rankine process are waste heat recovery processes.

[rjsa]

A turbine expanding hot exhaust gas and pumping juice into batteries is indeed a heat energy recovery system.

I guess there is some confusion on terminology around here, where some people might name systems based on temperature difference one thing, gas empansion another. Myself not being a native english speaker can't try to settle this.

[dren]

Would hot stagnant air turn the turbine?

[Holm86]

• Seventh your thermal efficiency improves by increasing engine and exhaust temperatures.

This is incorrect.

Thermal (Carnot) efficiency is defined as = (T1 - T2)/T1

Where
T1 is the temperature of the source (ie the combustion chamber) and
T2 is the temperature of the sink (ie exhaust)

Temperatures in Kelvin or Rankine.

So, lets say we have a combustion temperature of 1000K and exhaust of 650K. The efficiency is = (1000 - 650)/1000 = 35%

If we raise the exhaust temperature 100K we now get = (1000 - 750)/1000 = 25%.

If we increase the engine temperatures by the same as the exhaust temperatures we get:
= (1100 - 750)/1100 = 32%

Logically, if you have the same combustion temperatures and lower the exhaust temperatures you have extracted more energy from the combustion gases.

eg
= (1000 - 550)/1000 = 45%

Now, if you want to raise both the engine and exhaust temperatures to gain efficiency, the engine temperatures have to be raised more.

So, in my example, if we move the exhaust temperature up by 100K to 750K we have to raise the engine temperatures by at least 153.6K to get a gain in efficiency.

To get it up to 40% with a 100K exhaust temperature increase would require a 249.6K increase in engine temperatures.

The exhaust temperature should surely be measured after the turbine in a turbo engine right??

[wuzak]

The exhaust temperature should surely be measured after the turbine in a turbo engine right??

Yes.

Regardless, if that temperature rises the same, or a similar amount, to that in the combustion chamber, the efficiency is worse.