Honda Power Unit Hardware & Software

[etusch]

Guys watch the Pat Symonds video viewtopic.php?t=30363. The pre-chamber is in the wall of the main chamber and works as per the Mahle TJI system minus the extra injector in the pre-chamber.

There are 4 engine. Which one he is talking about ?


Can someone translate these?

[gruntguru]

His talk is generic. There are not significant deviations from the features he describes, in any of the engines.

[Roostfactor]

His talk is generic. There are not significant deviations from the features he describes, in any of the engines.

Please don't take offense as you are vastly more knowledgeable in this field than I am but there is certainly more than one way to accomplish tji type ignition.
@Sasha (I think) has some inside Honda knowledge and I heard directly from a highly knowledgeable birdie that Sasha is correct in stating the Honda version has a piston shaped like a volcano (think Mt. Fuji) with the pre chamber in the piston.
If injector was at the top then the injector could spray directly into the pre chamber then continue spraying to also fill the combustion chamber.
Seems like an efficient way to do it and potentially simpler and easier to get each chamber (pre and main cylinder) afr's exact.

[etusch]

But the video above, if it is real Honda F1 engine, there is a separate pre-chamber, passive or active. And it is not at the wall. I don't know, but keeping it at center, at engine head is more logical to me. I read some search papers from researchgate etc websites. They were experimented passive pre-chamber ignition system at road car engines. What I had see at them active pre-chamber has bigger potential to work leaner.
Passive pre-chamber has issues with egr system and at low rpm there is not enough mixture in combustion chamber to
fill pre-chamber to ignite. but when rpm goes higher and more fuel injected, it is better in road engines. They are interested with jets outing from nozzles. So if there is not atomized fuel in the air, there is no jet from pre-chamber which is not problem at F1 engine because of much more fuel they used.
So when F1 engine has no egr, and uses more fuel to get almost 1000 hp, working at higher rpm level, there is no problem for them to work with a passive pre-chamber. But I believe they choose the best way for this and if it is active one, I am sure they use active one.
I remember I shared here a video which tells how Mazda x engines work. They use supercharger to get desired amount of air in the cc, then inject little gasoline to get lean mixture, (their injectors located for injecting towards spark plug) and before ignition, they inject more fuel towards sp. I think there is specific piston crown shape to help them for doing this. ( maybe omega bowl shape like Pat Sysmonds talked about ) As Mazda's x engine works with compression ignition at some situations, I think this F1 engines also can be working compression ignition at some cases if not more than x engines. Especially with this E10 fuel.

[Dr. Acula]

So when F1 engine has no egr, and uses more fuel to get almost 1000 hp, working at higher rpm level, there is no problem for them to work with a passive pre-chamber. But I believe they choose the best way for this and if it is active one, I am sure they use active one.
I remember I shared here a video which tells how Mazda x engines work. They use supercharger to get desired amount of air in the cc, then inject little gasoline to get lean mixture, (their injectors located for injecting towards spark plug) and before ignition, they inject more fuel towards sp. I think there is specific piston crown shape to help them for doing this. ( maybe omega bowl shape like Pat Sysmonds talked about ) As Mazda's x engine works with compression ignition at some situations, I think this F1 engines also can be working compression ignition at some cases if not more than x engines. Especially with this E10 fuel.

It's the only way they could choose. The rules only allow one injector per cylinder, so an active prechamber was out of the question from the very start, unless one would have an intresting intepretation of the wording in the rules.

Compression ignition is also outruled btw.

[Sasha]

I heard Mercedes has there PC in the piston crown too and with Ferrari copy Mercedes and Honda and their large performance gain last year I bet they got rid of the Mahle system and moved the PC to the piston crown.

That is the big reason Mercedes was better than everyone else from day one.
They had experience with the diesel piston bowl CC design.
Remember back in 2015-16 that people was saying the MB was using compression ignition.
This is how you do it on the edges of the piston crown that leads to higher efficiency.

But I know nothing

[Sasha]

Remember when everyone laughed at me when I stated the PC will be larger than the Mahle system, alot larger.
Mahle system about 3%.
Piston crown system 10-25%
The bigger PC makes it easier to get higher CR and ignite most of fuel too for higher efficiency.

People kept on stating the heat problem of a very large PC in the head.

In the piston crown and there is no heat problem or scavenging problem.
The piston just needs good thermal coating and oil cooling.

[Roostfactor]

Remember when everyone laughed at me when I stated the PC will be larger than the Mahle system, alot larger.
Mahle system about 3%.
Piston crown system 10-25%
The bigger PC makes it easier to get higher CR and ignite most of fuel too for higher efficiency.

People kept on stating the heat problem of a very large PC in the head.

In the piston crown and there is no heat problem or scavenging problem.
The piston just needs good thermal coating and oil cooling.

One could also state the pc being active then sinse its moving as part of the piston?

[Sasha]

It is active because at almost TDC the PC in the piston crown is covered by the head.
Just enough space so very little fuel leaks out to make a very lean fuel mixture in the CC

[etusch]

It's the only way they could choose. The rules only allow one injector per cylinder, so an active prechamber was out of the question from the very start, unless one would have an intresting intepretation of the wording in the rules.

Compression ignition is also outruled btw.

If one injector per cylinder make active pre-chamber out of question, so where is the inventing new things ? Active pre-chamber with single injector is quite possible.

If compression ignition is banned just put there a spark plug and spark it every cycle. It is too easy and unfollowable.

[etusch]

I heard Mercedes has there PC in the piston crown too and with Ferrari copy Mercedes and Honda and their large performance gain last year I bet they got rid of the Mahle system and moved the PC to the piston crown.

That is the big reason Mercedes was better than everyone else from day one.
They had experience with the diesel piston bowl CC design.
Remember back in 2015-16 that people was saying the MB was using compression ignition.
This is how you do it on the edges of the piston crown that leads to higher efficiency.

But I know nothing

If I am not wrong Ferrari's performance increased after they introduced new ERS system but not after new engine. I don't remember it but if they updated IC engine too, still it didn't worked well until new ERS introduced at Russian Gp.
Ferrari was not that good except one year in turbo hybrid era, the year they had a deal with FIA. They are good this year with their engine power wise. Honda are best I think. But Merso is 3d if not 4th. So Merc's combustion concept is not best with E10. I assume that if Merso's combustion concept were used by Honda and Ferrari and only in this way they reached performance level of merc, they should be closer now. But as you can see, merc is clearly behind Ferrari and Honda maybe even renault.

[etusch]

Remember when everyone laughed at me when I stated the PC will be larger than the Mahle system, alot larger.
Mahle system about 3%.
Piston crown system 10-25%
The bigger PC makes it easier to get higher CR and ignite most of fuel too for higher efficiency.

People kept on stating the heat problem of a very large PC in the head.

In the piston crown and there is no heat problem or scavenging problem.
The piston just needs good thermal coating and oil cooling.

What you had said is logical at first glance. But if prechamber is on piston crown and if it became separate chamber at TDC, isn't it too late to ignite ? If I am not wrong even diesel engines injects fuel 5 degree before TDC.
When prechamber is on piston crown it can be larger but if it is separate chamber at head, it should be smaller because inside there will a combustion too.
If I am not wrong pre chamber is not only fast combustion but also combusting lean mixture to get more power. I read a few things and I remember something like %7 chamber volume but they were road car engines.
In the article I had read they were using cuCrZr at pre-chamber to handle heat. Maybe there is better options there.

[ryaan2904]

I heard Mercedes has there PC in the piston crown too and with Ferrari copy Mercedes and Honda and their large performance gain last year I bet they got rid of the Mahle system and moved the PC to the piston crown.

That is the big reason Mercedes was better than everyone else from day one.
They had experience with the diesel piston bowl CC design.
Remember back in 2015-16 that people was saying the MB was using compression ignition.
This is how you do it on the edges of the piston crown that leads to higher efficiency.

But I know nothing

If I am not wrong Ferrari's performance increased after they introduced new ERS system but not after new engine. I don't remember it but if they updated IC engine too, still it didn't worked well until new ERS introduced at Russian Gp.
Ferrari was not that good except one year in turbo hybrid era, the year they had a deal with FIA. They are good this year with their engine power wise. Honda are best I think. But Merso is 3d if not 4th. So Merc's combustion concept is not best with E10. I assume that if Merso's combustion concept were used by Honda and Ferrari and only in this way they reached performance level of merc, they should be closer now. But as you can see, merc is clearly behind Ferrari and Honda maybe even renault.

Didnt AmuS say Ferr were in the lead with ICE power since '22? About 5-10 hp lead they said.
Also, any idea why CI is banned in f1? I dont get why even an active pre-chamber or valve lift is banned here. It only serves the purpose of increasing efficiency. It think honda wouldve been in a much better position in '15 if these system were allowed

[mzso]

Can someone translate these?
https://i.ibb.co/QvtY4Z8/img-1370c7c604 ... 155428.jpg

Google Lens can. Does it not suffice?

[Hoffman900]

I heard Mercedes has there PC in the piston crown too and with Ferrari copy Mercedes and Honda and their large performance gain last year I bet they got rid of the Mahle system and moved the PC to the piston crown.

That is the big reason Mercedes was better than everyone else from day one.
They had experience with the diesel piston bowl CC design.
Remember back in 2015-16 that people was saying the MB was using compression ignition.
This is how you do it on the edges of the piston crown that leads to higher efficiency.

But I know nothing

If I am not wrong Ferrari's performance increased after they introduced new ERS system but not after new engine. I don't remember it but if they updated IC engine too, still it didn't worked well until new ERS introduced at Russian Gp.
Ferrari was not that good except one year in turbo hybrid era, the year they had a deal with FIA. They are good this year with their engine power wise. Honda are best I think. But Merso is 3d if not 4th. So Merc's combustion concept is not best with E10. I assume that if Merso's combustion concept were used by Honda and Ferrari and only in this way they reached performance level of merc, they should be closer now. But as you can see, merc is clearly behind Ferrari and Honda maybe even renault.

Didnt AmuS say Ferr were in the lead with ICE power since '22? About 5-10 hp lead they said.
Also, any idea why CI is banned in f1? I dont get why even an active pre-chamber or valve lift is banned here. It only serves the purpose of increasing efficiency. It think honda wouldve been in a much better position in '15 if these system were allowed

5-10hp on a 800bhp IC is around 1% tops. You wouldn't be able to differentiate that at speed from the data available, AMuS has no idea. At terminal speed, 10hp will be less than half a mph with the drag F1 cars have. 10hp over the 1000hp "all in" power is even less. Like, let's back up a second. Here are some older numbers for a F1 car: CD 0.98, FA: 14.33sq-ft, 702kg. A very rough back of the hand calculation results in 720hp drag / frictional loss (assuming aero force doubles the tire load) at 195mph. Change Cd from 0.98 to 1 and you kill 20hp at 195mph. So to deduce 5-10hp is near impossible without knowing exact aero and friction figures is near impossible.

Merc, Honda, Ferrari, and everyone else are using a rapid combustion, spark assisted (via the TJI) HCCI-like combustion concept. Audi pioneered this in the modern era with their fuel limited, high boost, Miller Cycle LeMans diesels in the late 2000s / early 2010s. All these engines are essentially gasoline riffs on them that rev higher and use a spark plug via the TJI. An Ilmor engineer has referred to these engines as "controlled detonation" engines, which I think is a better way of thinking of them. They are using cylinder pressure (boost and high static compression ratio) and rapid injection events with the injector in the TJI (and not always using the spark plug for all injection events) to set it off.

Audi also has a traditional DI engine in DTM that is also a rapid combustion engine, but is more traditional (Otto cycle, 102 octane pump gas). Running 16:1-20:1 AFR. Combustion duration is near half that of traditional Otto cycle, non-fuel flow limited, naturally aspirated engines.

In addition to Honda, the 066/7 Ferrari engine, that Wolf Zimmerman is credited for their rapid combustion concept, which is said to "exploit all of the 500 bar fuel pressure by the regulations in conjunction with more turbulence in the charge air and faster flame propagation". This "super fast concept" supposedly is utilizing up to five injections of fuel per cylinder / cycle. Reliability problems are apprently associated with the spark plug itself.

Most of this stuff is documented across several issues, across several years, of Race Engine Technology via interviews with people involved in these programs. None of this is really a secret among the engineers involved in these.

https://www.youtube.com/watch?v=KjrNcuc89Pc

The guy in this video claims that F1 engines uses passive pre chamber for combustion. What do you think about it ? When they run engines high rpms and good amount of fuel to fill a passive pre chamber it seems to me possible.

I don't really put much stock into what this guy says, about anything. Never really been a fan. If you want to learn what's going on, read Race Engine Technology, keep an eye out for University guest lectures, and SAE papers.

This pretty much tells you what these engines are doing: