Burning lean: Pre-chamber combustion tech

All that has to do with the power train, gearbox, clutch, fuels and lubricants, etc. Generally the mechanical side of Formula One.
blueytoo
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Joined: 02 Mar 2018, 23:37

Re: Burning lean: Pre-chamber combustion tech

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godlameroso wrote:
29 Mar 2018, 03:18
There's really only one way to do it with one injector and one spark plug, and the side injector is the big hint.
if such a thing exists, there must be a patent out there. the variable pattern injectors i can find are still symmetrical and omnidirectional.

seems a lot easier to put the injector on the boundary of the prechamber and main chamber.

blueytoo
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Joined: 02 Mar 2018, 23:37

Re: Burning lean: Pre-chamber combustion tech

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recent patent permits one injector in main chamber. prechamber ingests mixture in compression, assisted by richer mixture near prechamber apertures.
http://www.freepatentsonline.com/y2017/0096932.html

johnny comelately
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Joined: 10 Apr 2015, 00:55
Location: Australia

Re: Burning lean: Pre-chamber combustion tech

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Could posters say what they think the overall (if the chamber is not homogenised) lambda is for steady state and transition please:

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godlameroso
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Location: Miami FL

Re: Burning lean: Pre-chamber combustion tech

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johnny comelately wrote:
29 Mar 2018, 13:39
Could posters say what they think the overall (if the chamber is not homogenised) lambda is for steady state and transition please:
The only ones that know are the ones tuning the fuel tables.
Saishū kōnā

johnny comelately
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Location: Australia

Re: Burning lean: Pre-chamber combustion tech

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godlameroso wrote:
29 Mar 2018, 20:47
johnny comelately wrote:
29 Mar 2018, 13:39
Could posters say what they think the overall (if the chamber is not homogenised) lambda is for steady state and transition please:
The only ones that know are the ones tuning the fuel tables.
OK yes, but what do you think it is?

Tommy Cookers
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Joined: 17 Feb 2012, 16:55

Re: Burning lean: Pre-chamber combustion tech

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1.5 - with conventional valve working and conventional VE

though VE restriction via unconventional IV period could give near 1 lambda with the apparent 4 bar absolute 'boost'

Muniix
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Joined: 29 Nov 2016, 13:29
Location: Sydney, Australia

Re: Burning lean: Pre-chamber combustion tech

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johnny comelately wrote:
29 Mar 2018, 23:34
godlameroso wrote:
29 Mar 2018, 20:47
johnny comelately wrote:
29 Mar 2018, 13:39
Could posters say what they think the overall (if the chamber is not homogenised) lambda is for steady state and transition please:
The only ones that know are the ones tuning the fuel tables.
OK yes, but what do you think it is?
I'd guess 1.6 - 1.85. Maximum Thermal efficiency would be closer to 1.8, the high boost pressure above 3.5 bar in small 266cc cylinders and the bore to stroke ratio giving it high peak pressure to mean, high BSR reduces this.
The side mount injection would be chosen for turbulence enhancement possible for non premixed secondary injection after TDC.

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godlameroso
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Joined: 16 Jan 2010, 21:27
Location: Miami FL

Re: Burning lean: Pre-chamber combustion tech

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What about injector flow per pulse? Surely it's spraying more than once or twice per engine cycle. They must have had lots of issues with injector dribbling at first. Maintaining accurate spray and droplet size becomes challenging at the time scales involved, even with piezoelectric control. Particularly(pun intended)with a 500 bar pressure limit.

There's a lot of development just engineering better injectors, I'd say 30% of current power gains have come just from the injectors, and the fuel system in general. Ironic then that in cost conscious F1 this area is pretty much a bottomless money pit, add to the fact that this is not an area that incurs grid penalties so the manufacturers are free to upgrade this system throughout the season.
Saishū kōnā