2014-2020 Formula One 1.6l V6 turbo engine formula

[WhiteBlue]

Actually the injectors are not standardized design any more. But I agree that any hydraulic accumulator function for flow increase would be against the intention of the rules. If I remember it right the fuel pressure has to be generated by a high pressure piston pump and hydraulic accumulation is not allowed. I will have a look.
And here it is:

5.10 Fuel systems :
5.10.1 The pressure of the fuel supplied to the injectors may not exceed 500bar.
5.10.2 There may only be one direct injector per cylinder and no injectors are permitted upstream of the intake valves or downstream of the exhaust valves.
5.10.3 Homologated sensors must be fitted which directly measure the pressure, the temperature and the flow of the fuel supplied to the injectors, these signals must be supplied to the FIA data logger.
5.10.5 Only one homologated FIA fuel flow sensor may be fitted to the car which must be placed wholly within the fuel tank.
5.10.6 Any device, system or procedure the purpose and/or effect of which is to increase the flow rate after the measurement point is prohibited.

The fuel flow must be measured in the fuel tank (which is obviously non pressurized) and it will be controlled by telemetry. The flow of fuel to all single direct injectors will also be controlled and presumably be integrated for further control purposes. Accumulation is prohibited by paragraph 5.10.6 which makes any increase in flow rate beyond the in tank measurement illegal. Or rather if you use accumulation the competitor must make sure that the legal fuel flow is not exceeded. I assume that the FiA will have a rather close look at the integrated data to see if they match the tank fuel flow. It should be obvious if a competitor cheats with accumulated injector pulsing.

[PlatinumZealot]

do they allow a "buffer" after the fuel meter? for example if the flow limit is 100% and at low rpm/off -throttle they need only 60%, could they store the unused 40% and use it for a "100+40" boost at the next acceleration?

2014 regulations say (p. 5.8.3) that the flow of the fuel supplied to the injectors has to be measured. So the measurement will be taken after the pump, at the high pressure line to the injector. Since liquids are practically non-compressible I don't think that such "buffer" is possible.

you just need to have an "air bubble" or bladder with compressed gas, say nitrogen, in the buffer tank. that is how hydraulic buffers work

but I'm sure all those parts will be strictly controlled

This is easy. You only need a fuel return line and put the flow meter after the return. This is commonly done on boilers with fuel flow meters. There will be no excess. You probably put a flow regulator after the return line.

[Tommy Cookers]

But I agree that any hydraulic accumulator function for flow increase would be against the intention of the rules

5.10 Fuel systems :
5.10.3 Homologated sensors must be fitted which directly measure the pressure, the temperature and the flow of the fuel supplied to the injectors, these signals must be supplied to the FIA data logger.
5.10.5 Only one homologated FIA fuel flow sensor may be fitted to the car which must be placed wholly within the fuel tank.
5.10.6 Any device, system or procedure the purpose and/or effect of which is to increase the flow rate after the measurement point is prohibited.

The fuel flow must be measured in the fuel tank (which is obviously non pressurized) and it will be controlled by telemetry. The flow of fuel to all single direct injectors will also be controlled and presumably be integrated for further control purposes. Accumulation is prohibited by paragraph 5.10.6 which makes any increase in flow rate beyond the in tank measurement illegal. Or rather if you use accumulation the competitor must make sure that the legal fuel flow is not exceeded. I assume that the FiA will have a rather close look at the integrated data to see if they match the tank fuel flow. It should be obvious if a competitor cheats with accumulated injector pulsing.

so a different story seems to be emerging ?
eg any time the engine is doing 10500 rpm or more it can draw fuel at the maximum rate, but need not burn it at that rate
so some fuel can be briefly held back eg to allow the fuel burn rate to increase as rpm progress beyond 10500
even at max rpm going to a burn rate slightly beyond the maximun supply rate
(the mean fuel burn rate of the 10500+ time not exceeding the mandated fixed fuel supply rate for 10500+)

so the engine CAN be run with at a constant best mep, constant best mixture, and constant best efficiency as rpm rises and falls !
(and produce constant axle torque with speed increase, not a falling torque with speed increase)

these rules make sense, presumably their apparent evolution is due to the influence of the engine manufacturers
how else could the engine be efficiently used with a pool of only 8 (overall) ratios to cover the whole season ?

[WhiteBlue]

5.10.6 Any device, system or procedure the purpose and/or effect of which is to increase the flow rate after the measurement point is prohibited.

so some fuel can be briefly held back eg to allow the fuel burn rate to increase as rpm progress beyond 10500
even at max rpm going to a burn rate slightly beyond the maximun supply rate

I'm surprised that you think that would be legal.

[Tommy Cookers]

eg any time the engine is doing 10500 rpm or more it can draw fuel at the maximum rate, but need not burn it at that rate
so some fuel can be briefly held back eg to allow the fuel burn rate to increase as rpm progress beyond 10500
(the mean fuel burn rate of the 10500+ time not exceeding the mandated fixed fuel supply rate for 10500+)

you seem to have (when quoting my post) again edited out something important to the post
your post in part surely implies that it would be legal
also it makes sense

[WhiteBlue]

eg any time the engine is doing 10500 rpm or more it can draw fuel at the maximum rate, but need not burn it at that rate
so some fuel can be briefly held back eg to allow the fuel burn rate to increase as rpm progress beyond 10500
(the mean fuel burn rate of the 10500+ time not exceeding the mandated fixed fuel supply rate for 10500+)

you seem to have (when quoting my post) again edited out something important to the post
your post in part surely implies that it would be legal
also it makes sense

I'm sorry if you think that I have tried to manipulate your post. That was not my intention. I just tried to focus on the relevant parts. I don't think that any rationalizing gets you around that regulation. Any attempt to generate a flow exceeding the regulated maximum or to "burn it" as you say will be illegal. In my view the regulation is water tight.

[FW17]

Does anyone have the efficiency figures for the current irl Chevrolet and Honda engines?

[garrett]

I hope with different cost control mechanisms we will see a revival of the old turbo age when different engine concepts were still possible and were competing against each other.

It could be possible if the new regulations are established and a kind of a CCA is found we could see at least the possibility of using inline four engines in the upcoming years, of course with some equivalence formula. Formula 1 as a pinnacle of motorsport, for me it was the development of the BMW M10/12 four inline from the road car equivalent to the most powerful F1 engine ever-that´s F1!

About Ferrari, it´s an open secret they forgot about pride in 1985 and - facing the 195 l formula - even considered an inline four in Maranello, but there was no way to do it with Enzo still in power. So they shouldn´t be hypocrite. (Same time, Cosworth paralelly wanted to build a V6 for 220 l plus an I4 for the 195 l). So Montezemolo should have known better than bashing the 4 and V6 concept, because Ferrari has shown being capable of building excellent V6-turbo engines too (the Tipo 032 of 1986 was the second strongest of the year after the BMW).

[Tommy Cookers]

Audi had FSI (Fuel Stratified Injection) in racing years before it went into their roadcars. Was that just a marketing gimmic to call the racing version FSI as well?? Or did they actually use stratified injection in the race engines??

It was at Le Mans where gas milage is very important as well.

saw something on this where the Audi man said that the mean mixture was stoichiometric and the core mixture was richer (richer giving faster combustion, so gaining efficiency)
I shall try to remember this !

[WhiteBlue]

Audi's FSI technology was wall and air guided combustion, at least the part that was commercialized. They never exceeded 125 bar injection pressure. The next systems should have much higher pressure and are likely spray guided combustion or similar to that concept.

[Edis]

you just need to have an "air bubble" or bladder with compressed gas, say nitrogen, in the buffer tank. that is how hydraulic buffers work

There's no such thing as "air bubble" at 500 bar. I've quickly checked several gases and they are either liquid or supercritical fluid at 500 bar at normal temperature.

The regulations say that flow "supplied to the injectors" has to be measured, not supplied to the bladder or something else. And the injectors have to be homologated by FIA. I really see little room for "clever" solutions.

He was referring to attaching one of these to the fuel rail, a hydraulic accumulator:



They are used to temporarily increase the fluid flow. When the demand is lower than the flow from the pump the accumulator is filled, and when the demand is higher than the flow from the pump the accumulator supplies part of the fluid flow using either gas pressure or a mechanical spring. I guess you could hide a really small one inside the fuel rail.

[WhiteBlue]

Piston or bladder accumulators are equally capable to boost the flow speed, but their use would be prohibited by the rule that I have quoted several times. The rules say that the flow of petrol is limited. It says that the flow has to be measured a first time in the fuel tank (when it is still on low pressure) and it says the fuel flow has to be measured at every one of the six direct injectors. Finally it specifies that any attempt to increase the fuel flow above the measured flow or any device with the aim of doing that is illegal. So you can use an accumulator but it must not increase the flow rate, which defeats it's main objective.

[Tommy Cookers]

5.10 Fuel systems :
5.10.3 Homologated sensors must be fitted which directly measure the pressure, the temperature and the flow of the fuel supplied to the injectors, these signals must be supplied to the FIA data logger.
5.10.5 Only one homologated FIA fuel flow sensor may be fitted to the car which must be placed wholly within the fuel tank.
5.10.6 Any device, system or procedure the purpose and/or effect of which is to increase the flow rate after the measurement point is prohibited.
so a different story seems to be emerging ?
eg any time the engine is doing 10500 rpm or more it can draw fuel at the maximum rate, but need not burn it at that rate
so some fuel can be briefly held back eg to allow the fuel burn rate to increase as rpm progress beyond 10500
even at max rpm going to a burn rate slightly beyond the maximun supply rate
(the mean fuel burn rate of the 10500+ time not exceeding the mandated fixed fuel supply rate for 10500+)
so the engine CAN be run with at a constant best mep, constant best mixture, and constant best efficiency as rpm rises and falls !
these rules make sense, presumably their apparent evolution is due to the influence of the engine manufacturers
how else could the engine be efficiently used with a pool of only 8 (overall) ratios to cover the whole season ?

IMO
for the above to be workable about !cc of fuel held back from injection for about 1 second would typically be sufficient

the injection rate, even from any 1 injector must be and will be much higher than the fuel supply rate
(the injection period will probably be less than 10 deg of crankshaft rotation, and cannot be more than about 60 deg)
clearly rule 5.10.3 devices are not defined as able to supervene the rule 5.10.5, the master measurement

the master measurement is of a (relatively steady) fuel rate at very small pressures in the tank
fuel is then compressed to 200-500 bar ! (heated/cooled) then drawn intermittently from the engines casting 'common rail' reservoir
necessarily the peak massflow will be higher than the fuel tank supply rate

any real-world system will have enough inherent 'mass/time compliance' to be useable as above, without any illegal devices
(due to interrmittency, compressibility, expansion, dissolved atmospheric or gases intentionally dissolved as fuel etc etc)
(and mechanical compliance)

it seems clear that rules intent was to allow operation as above, and the rules cannot prevent such operation anyway

the rules were intended to prevent the harvesting of significant fuel eg under braking and cornering
(when the engine could easily be run eg at 10500 rpm for this purpose)
the rules will prevent that

they were never intended to prevent the engines being run on the chosen mixture strength over the normal and necessary rpm range

[autogyro]

Nothing prevents you from cutting off the engine completely in coast conditions if you want to 'harvest' fuel.
Zero fuel flow is not against the regulations.

[langwadt]

you just need to have an "air bubble" or bladder with compressed gas, say nitrogen, in the buffer tank. that is how hydraulic buffers work

There's no such thing as "air bubble" at 500 bar. I've quickly checked several gases and they are either liquid or supercritical fluid at 500 bar at normal temperature.

The regulations say that flow "supplied to the injectors" has to be measured, not supplied to the bladder or something else. And the injectors have to be homologated by FIA. I really see little room for "clever" solutions.

He was referring to attaching one of these to the fuel rail, a hydraulic accumulator:



They are used to temporarily increase the fluid flow. When the demand is lower than the flow from the pump the accumulator is filled, and when the demand is higher than the flow from the pump the accumulator supplies part of the fluid flow using either gas pressure or a mechanical spring. I guess you could hide a really small one inside the fuel rail.

as piast points out there is no gasses at 500bar, so you'd need something like 1:10 "gearing" between the liquid piston size and the gas piston size and you'd need a substantially larger volume on the gas side to keep the pressure change, from full to empty, down