2014-2020 Formula One 1.6l V6 turbo engine formula

[Holm86]

I also think there is a large overlap on the engines now. But thats because they are naturally aspirated. They take advantage of exhaust scavenging which uses overlap to help suck in more air from the low pressure zones created after the exhaust pulse.

You naturally dont use that much overlap in turbo engines as the turbo forces the air into the cylinders.

[rjsa]

Wouldn't the use of direct injection benefit from some overlap? You can garantee proper wash out of burnt gases and inject after the exhaust is closed, avoiding pumping unburnt fuel thru the exhaust.

[Holm86]

Wouldn't the use of direct injection benefit from some overlap? You can garantee proper wash out of burnt gases and inject after the exhaust is closed, avoiding pumping unburnt fuel thru the exhaust.

There will be a small overlap no doubt. And that would be enough to flush the combustion chamber and not blow to much air into the exhaust.

[tuj]

With this talk of overlap, certainly the turbo design will be twin-scroll, no? That should avoid any issues of exhaust-pulse interference.

[ringo]

All that complication mention, when all you need is a simple waste gate.
As for the boost pressure, Marmorini seems to mention the boost when it's highest which is in the low rpm range.

[wuzak]

All that complication mention, when all you need is a simple power waste gate.
As for the boost pressure, Marmorini seems to mention the boost when it's highest which is in the low rpm range.

There, fixed.

[Holm86]

All that complication mention, when all you need is a simple waste gate.
As for the boost pressure, Marmorini seems to mention the boost when it's highest which is in the low rpm range.

Using a waste gate to bleed some of the backpressure would leave you with lower pressure both before and after the turbine. Which would decrease the efficiency quite a bit.

[Kiril Varbanov]

Renault engine 2014 - charging and discharging of ERS

[youtube]http://www.youtube.com/watch?v=0UKtPWfecqE[/youtube]

[Tommy Cookers]

agreed, induction pressure (abs boost) does not need to increase with increased exhaust pressure associated with recovery
broadly speaking, the valves isolate the upstream from activities downstream
this isolation should be better in these new turbo-compound engines (than in the 1940s TC aero engines)
the 2014 engines having about half the combustion chamber volume (relatively) ie about twice the CR
there is relatively little dead volume (though scavenge is no longer particularly important ie under 2014 rules)

what I can't forget is that last year people produced supercharging powers of about 25 hp at 15000 and 45 hp at 10500
and we were all happy with these figures, bearing in mind that supercharging hp costs recovery hp
these figures seemed to suggest that supercharging power increased with boost despite the constant massflow

EDIT (after Wuzak's post following this)
the supercharging flow work is of course the work to fill the cylinders beyond the N/A level
so the supercharging work as rpm increases from 10500 falls faster than the rpm increase
(ie if the engine did eg 20000 rpm it would reach the required air massflow with N/A)
supercharging work is P gauge x dV = constant
this fits the power figures given above

[wuzak]

what I can't forget is that last year people produced supercharging powers of about 25 hp at 15000 and 45 hp at 10500
and we were all happy with these figures, bearing in mind that supercharging hp costs recovery hp
these figures seemed to suggest that supercharging power increased with boost despite the constant massflow

Of course, since producing higher boost requires more work to be done to the air.

[Owen.C93]

Wait, is the HERS powering the compressor when it's discharing? Why not send the power straight to the crank?

[1158]

Wait, is the HERS powering the compressor when it's discharing? Why not send the power straight to the crank?

Well I guess it could be used to help spool up the compressor, eliminating lag.

I wonder the opposite. I brought up the use of boost by gear to help with traction a few months ago and after it was discussed in the thread it didn't seem like it would be possible to pull it off.

Now I am wondering if under acceleration the compressor shaft could be braked to harvest some energy and thus limit boost and power and provide what would mimic traction control out of slower corners. Could something like this be used at the start? It would require setup work for each gear/track in the simulator, but I don't see why it couldn't be done. Are there any limits to when energy can be harvested? Other than that I cannot see how this would be against the regulations.

[garrett]

When Porsche built that V12 monstrosity didn't they just try to glue two V6s together?

Yes, and the 3512 engine was conceived after the 912 type with unusual method of drawing power from the centre of the engine which led to big oil pressure problems. Furthermore, the oil tank was too small (9 instead of 12 litres). As the Arrows was finished too late by Alan Jenkins because of the Mercedes talks and Arrows and Porsche didn´t cooperate, the engine had to be finished without knowledge of the car. So, being too long and too heavy, a transversal gearbox had to be implemented. These developments led to the disaster...

[xpensive]

When Porsche built that V12 monstrosity didn't they just try to glue two V6s together?

Yes, and the 3512 engine was conceived after the 912 type with unusual method of drawing power from the centre of the engine which led to big oil pressure problems. Furthermore, the oil tank was too small (9 instead of 12 litres). As the Arrows was finished too late by Alan Jenkins because of the Mercedes talks and Arrows and Porsche didn´t cooperate, the engine had to be finished without knowledge of the car. So, being too long and too heavy, a transversal gearbox had to be implemented. These developments led to the disaster...

It was also pitifully down on power, while Alan Jenkins surely was no John Barnard in telling Hans Mezger what to do.

[chip engineer]

agreed, induction pressure (abs boost) does not need to increase with increased exhaust pressure associated with recovery
broadly speaking, the valves isolate the upstream from activities downstream
this isolation should be better in these new turbo-compound engines (than in the 1940s TC aero engines)
the 2014 engines having about half the combustion chamber volume (relatively) ie about twice the CR
there is relatively little dead volume (though scavenge is no longer particularly important ie under 2014 rules)

what I can't forget is that last year people produced supercharging powers of about 25 hp at 15000 and 45 hp at 10500
and we were all happy with these figures, bearing in mind that supercharging hp costs recovery hp
these figures seemed to suggest that supercharging power increased with boost despite the constant massflow

EDIT (after Wuzak's post following this)
the supercharging flow work is of course the work to fill the cylinders beyond the N/A level
so the supercharging work as rpm increases from 10500 falls faster than the rpm increase
(ie if the engine did eg 20000 rpm it would reach the required air massflow with N/A)
supercharging work is P gauge x dV = constant
this fits the power figures given above

Since:
1. massflow of the intake and exhaust is constant over the 10500 to 15000 rpm range, and
2. there is probably an optimum back pressure for best power (total from engine and MGUK) that is fairly independent of rpm over the 10500 to 15000 range, and
3. required boost pressure decreases considerably as rpm increases,

I can see why some think a wastegate would be useful to avoid back pressure increase at high rpm.

An alternative that could reduce drag from a very large air to air intercooler would be to us two much smaller intercoolers in series. The first would be water cooled and only operate its pump at low rpm (max flow at 10500 and continuously reduce flow to 15000) and 'store' its cooling capacity at high rpm (the low duty cycle allowing a smaller radiator). The second small air to air intercooler would operate continuously.

The reduced cooling at high rpm would keep the pressure required to be produced by the compressor relatively constant over rpm range, eliminating any need for a wastegate. The energy that would have been wasted by the wastegate effectively is used to reduce drag (smaller total intercooler size).