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fuel mix with burning oil


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#1 pierrre

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Posted 18 July 2017 - 03:47

ive got no clue on how they extract more power from doing this. maybe better prevention of detonation? seems that f1 teams are burning oil and mixing it with its fuel and the fia started clamping down on this

 

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#2 gruntguru

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Posted 18 July 2017 - 11:39

The rules only permit 100 kg/hr maximum fuel flow rate. This restricts the power to whatever percentage of the energy in that fuel, the engine is able to convert. (100 kg/hr is about 1250 kW so a 50% engine efficiency yields about 625 kW). If 5 kg/hr of oil is added to the air/fuel mix and that oil can be combusted efficiently, the total energy input becomes 1312 kW and the power output becomes 656 kW - an increase of 31 kW.



#3 Kelpiecross

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Posted 21 July 2017 - 06:11


I have seen old, worn-out diesels running on their own sump oil - but I don't know about this. There would seem to be so many problems in arranging this that it would not be practical - possibly a smokescreen (so to speak) for whatever other cheating is going on.

#4 Charlieman

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Posted 21 July 2017 - 11:54

If 5 kg/hr of oil is added to the air/fuel mix and that oil can be combusted efficiently, the total energy input becomes 1312 kW and the power output becomes 656 kW - an increase of 31 kW.

Let's try to design a better way to cheat by burning oil in this way. 

 

You wouldn't want to carry 8kg of extra oil at the start of a race. The top speed benefit -- a cube of power output -- is not sufficient to make it work.

 

You might accept 0.5kg for opportunistic use during the race. 5mph faster in a straight line once the car has burned a bit of fuel. That means you have to design a cheat system somewhere that can't be detected by the standard ECU.



#5 Cavalier53

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Posted 24 July 2017 - 17:48

I understand the trick would be used specifically for (final) qualifying. Then in the example of 5 kg/hr, just 83 grams for a minute of full throttle a lap, 31 kW extra would bring a few tenths, wouldn't it? Worth a row or two on the grid, or the pole!

 

Even at 10 minutes for 2 stints in Q3, it would require about 0.85 kg or just 1 litre, depending on what actually are the components in nowadays F1 "oil".

 

But how does the oil end up in the combustion chamber? Regardless even of the ECU, the lean engines will get a power boost if there is anything extra to get burnt...


Edited by Cavalier53, 24 July 2017 - 17:50.


#6 jimjimjeroo

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Posted 24 July 2017 - 17:51

Chemicals in the oil. Chemicals in the fuel.

Suck squirt BANG BANG.

im guessing there's fancy additives in oil which can't be transferred as well in fuel

#7 Greg Locock

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Posted 24 July 2017 - 20:03

How does oil get into the combustion chamber? valve guides, piston rings, or an injector somewhere into the intake.



#8 GreenMachine

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Posted 25 July 2017 - 03:33

I'd use the oil seal on the compressor bearing, to 'not-seal' by a calculated amount ...  ;)



#9 bigleagueslider

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Posted 25 July 2017 - 03:39

One article mentioned that oil vapor from the sump was being fed to the intake through a breather system. I can imagine some volatile chemical added to the lube oil that boils off as the oil gets hot, gets mixed with the intake air charge, and then combusts efficiently in the engine. Remember how the old piston aircraft engines mixed fuel with the lube oil to thin it out in cold conditions to make starting easier? As the oil heated up the fuel would boil off and get burned by the engine.



#10 MatsNorway

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Posted 25 July 2017 - 15:50

I would think they ran some kind of octane boost in the oil.. Allowing higher comp.



#11 Kelpiecross

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Posted 26 July 2017 - 06:50


If they are doing this they are pretty clever. Anything resembling normal oil would make huge amounts of smoke, ruin the octane rating and maybe not burn fast enough. But it also has to act as a very high quality lubricant as well in a highly-stressed engine. The Hungarian GP at the weekend will be interesting to see if they still have a bit of extra qualifying power.

#12 thegforcemaybewithyou

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Posted 27 July 2017 - 09:46

Btw, there a small changes to the fuel regulations in the 2018 regulations. http://www.fia.com/r...on/category/110

 

In §19.2 Definitions

 

"Aromatics - Monocyclic and bicyclic aromatic rings with or without paraffinic or olefinic side chains. Only one double bond may be present outside the aromatic ring."

is changed into

 

"Aromatics - Monocyclic and bicyclic aromatic rings with or without paraffinic side chains."

 

 

In this section there's alos an addition for 2018 about metals.

 

"Metals

Metals are defined as alkali metals, alkaline earth metals, transition metals, actinides, lanthanides, post-transition metals and metalloids.
Alkali Metals Group 1 elements, excluding hydrogen."

 

 

In §19.3 Properties

 

"Manganese                                  mg/l 2.0    ASTM D 3831 or ICP-OES
Metals (excluding alkali metals)    mg/l 5.0    ICP-OES"

limits have been added.

 

And in §19.4.1 Composition, the limits for

 

"Total di-olefins                                  wt% 0.1    GCMS
Total styrene and alkyl derivatives    wt% 0.1    GCMS"

have been reduced from 1%.

 

 

Any connections to this engine oil topic?



#13 Lee Nicolle

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Posted 12 August 2017 - 00:02

F1 spends millions on very small 'cheats'

 Seemingly with input from the oil manufacturers. 

As most of us know oil causes detonation so in a race engine you make all efforts to avoid it contaminating the combustion.

Crankcase ventilation would seem to be the way to do it but how do you meter it?



#14 Charlieman

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Posted 12 August 2017 - 12:40

Crankcase ventilation would seem to be the way to do it but how do you meter it?

And how do you prevent it showing up in logs for the ECU? How do you explain different temperature patterns and different mixtures when the ECU responds to combustion sensors?



#15 desmo

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Posted 16 August 2017 - 14:15

F1 crankcase breathers vent into the airbox, I've wondered how that pulsed venting might interact with the wave chaos already happening inside it.



#16 Magoo

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Posted 02 October 2017 - 00:36

The practice reminds me of a runaway diesel eating up its own lubricating oil.