Honda Power Unit Hardware & Software

[mzso]

Road engines have followed a very similar trajectory of increasing efficiency via turbos, higher pressures, higher temperatures and higher levels of such emissions that filters and converters then have to manage, although there is an amusing piece of propaganda floating around that this only happens to diesel vehicles.

This should not really be a big shock to anyone.

This is another thing that shows that, sadly F1 follows the precedents set by road technology rather than innovating anything. Despite their claim for the opposite, and being some sort of "pinnacle".

[mzso]

The way I understand it is, reforming the fuel as specified is changing the fuel specification when used.

So is burning the fuel. This bears no relevance to what fuel they pump in the tanks. Unless fuel reforming is explicitly banned this should be entirely possible.

[rogazilla]

This is another thing that shows that, sadly F1 follows the precedents set by road technology rather than innovating anything. Despite their claim for the opposite, and being some sort of "pinnacle".

That's very unfair to say that. You can always deduce down to the engine still has cylinders, pistons and spark plugs and that's hardly innovating anything. Whether something has its root from road tech or invented on the track, it is what limit they push the tech to makes it a pinnacle series.

The car manufactures R&D exists first and foremost to try to turn it into a product someday and make profit. Therefore it hardly really matter if any tech started from road or track.

[Tommy Cookers]

- this seems to be fuel reforming, is this allowed in F1?:

some fuel reforming always occurs in rich mixture regions
so it will be temporary or continuous according to the duration of the rich mixture combustion

the chemistry (competition for oxygen) favours carbon over hydrogen
ie rich mixture produces CO (dissociation of CO2), CH4, and even H2 (dissociation of H2O ?)
for combustion later if/when further oxygen becomes available
(takeoff Wright TC exhausted as hydrogen 14.2% of original fuel value and 31.8% as CO - cruise 1.5% as CH4 and 3.1% as CO)

these gasses will support leaner combustion than would the original liquid fuel
the F1 engine could combust post-cylinder/pre-turbine

[godlameroso]

Rumour says Honda have been working with Exxon for 2019 on a new Honda development where the fuel passes through a device to give it an extra kick.

So Googling, and an article from 2016 popped up - this seems to be fuel reforming, is this allowed in F1?:

https://tech.nikkeibp.co.jp/dm/atclen/n ... 041500509/

Specifically, gasoline fuel and exhaust gas are turned into hydrogen by using a catalyst, and the hydrogen is mixed with intake air. The combustion speed of hydrogen is very high, making the combustion in the engine cylinders faster. When a larger amount of exhaust gas is returned to the engine cylinders for EGR, combustion becomes difficult while fuel efficiency improves. The method can solve this problem.

Honda Motor Co Ltd is making efforts to develop a method that is different from the method of producing hydrogen.

I did came upon this interesting fuel reforming subject being set upon mostly by Japanese automakers including Honda. But I could not see how this fuel reforming will involve Honda F1 project because as long as Honda is involved in F1 it will have to abide by the F1 rules and regulations as regards the fuel used in F1. The way I understand it is, reforming the fuel as specified is changing the fuel specification when used.

The regulations allow 2 specs of fuel to be used per weekend.

19.7.1 Before any fuel may be used in an Event, two separate five litre samples, in suitable containers,
must be submitted to the FIA for analysis and approval.

19.7.3 No competitor may have more than five fuel formulations approved for use during a
Championship season.

19.7.4 No competitor may have more than two approved fuels available during an Event.

[subcritical71]

The way I understand it is, reforming the fuel as specified is changing the fuel specification when used.

So is burning the fuel. This bears no relevance to what fuel they pump in the tanks. Unless fuel reforming is explicitly banned this should be entirely possible.

My interpretation would be that it would not be allowed, but for different reasons. The fuel specification as homologated is tested via one liter sample will still be as homologated. Its the fuel downstream of the catalyst that would have a different specification, but like introducing air to the fuel in the combustion chamber this is not considered changing the fuel specification.

The parts that don't conform as described is the introduction of H2 into the intake as 5.14.1 seems to indicate that would not be allowed(?). Could the H2 be injected before the intake? Would the FIA not see H2 as air since it is technically a gas, but it is part of 'airs' makeup? 5.14.2 seems to allow it(?) since the H2 would have been part of the fuel originally.

The other issue is using the exhaust as part of this system could be seen as an EGR system which is also not allowed per 5.14.2.

I would also think that the use of a catalyst in the fuel system to be a bit dodgy, but I don't know what rule that would violate.

And an FYI... the 2019 Technical Regulations were updated in December (published 20 Dec 2018, dated 5 Dec 2018). I haven't had time to see what changed but from what I've seen it looks like someone butchered the formatting in the newer version.

5.14 Engine intake air :
5.14.1 With the exception of incidental leakage through joints or cooling ducts in the inlet system (either into or out of the system), all air entering the engine must enter the bodywork through a maximum of two inlets which are located:
a) Between the front of the cockpit entry template and a point 500mm forward of the rear wheel centre line longitudinally.
b) No less than 200mm above the reference plane vertically.
c) On vertical cross-sections parallel to C-C.
Furthermore, any such inlets must be visible in their entirety when viewed from the front of the car without the driver seated in the car and with the secondary roll structure and associated fairing removed (see Article 15.2.6).
5.14.2 The addition of any substance other than fuel, as described in Article 5.10.3, into the air destined for combustion is forbidden. Exhaust gas recirculation is forbidden.

[dren]

You could have some form of EGR through valve timing, but why would you want that?

[Tommy Cookers]

internal 'EGR' (retention) with suitable fixed valve timing - by manipulation of the exhaust 'back' pressure vs forward pressure

why wouldn't you want that ? (at times)
less pumping loss and more conservation of heat

the PU is a compound engine with a weak 2nd stage (of heat addition & expansion)
there is no hard limit of the capacity of the 2nd stage


btw is the burning of nitrogen to NOx exothermic ? - a nice trick if air's main constituents combine and produce heat

[kasio]

btw is the burning of nitrogen to NOx exothermic ? - a nice trick if air's main constituents combine and produce heat

This was interesting question and i looked it up. It appears it is opposite - endothermic (it takes heat)

[godlameroso]

A good way to remeber it. Breaking bonds absorbs energy, IE when you break up with a girl you get depressed. Forming bonds releases energy, IE when you hook up with a girl you become all happy and energetic.

[dren]

Triple bonded N2 has a high bond enthalpy, I'm guessing that's why high temps are required for NOx formation.

[restless]

If N^2 to NOX reaction was exothermic, making fire anywhere on Earth would be quite a show

[PlatinumZealot]

That graph is at lamda = 1. My common senss tell me the graph title is a typo.

The graph title (% NOx Reduction over Baseline SI (lambda=1)) simply means "% NOx Reduction over Baseline SI".

The "(lambda=1)" is just telling us that the baseline SI engine readings were taken at lambda=1.

Who said it wasn't at Lambda 1?

The title says "Percent reduction" which can mislead overenthusiastic readers when they see 99% "reduction" on the graph! It more like fractions of a percent reduction.

And that is my point. He should have look across the entire lambda range on the other graph on the right before jumping to the conclusion that TJI make 99% less NOx. For similar lamda the NOx is almost the same. Honda has Lean burn standard ignition engines that are low NOx, but naturally the SAE study would not have that data to compare with TJI at higher Lambda values.

[PlatinumZealot]

- this seems to be fuel reforming, is this allowed in F1?:

some fuel reforming always occurs in rich mixture regions
so it will be temporary or continuous according to the duration of the rich mixture combustion

the chemistry (competition for oxygen) favours carbon over hydrogen
ie rich mixture produces CO (dissociation of CO2), CH4, and even H2 (dissociation of H2O ?)
for combustion later if/when further oxygen becomes available
(takeoff Wright TC exhausted as hydrogen 14.2% of original fuel value and 31.8% as CO - cruise 1.5% as CH4 and 3.1% as CO)

these gasses will support leaner combustion than would the original liquid fuel
the F1 engine could combust post-cylinder/pre-turbine

When the hydrogen is formed though... what happens to the residual carbon?

[Tommy Cookers]

all the carbon burns to CO2 or CO (is what I've been suggesting)
certainly iirc there was little or no visible carbon particulate
the CH4 and H2 have lost their partner carbon and oxygen
the small CH4 content of the exhaust occurs with any mixture, the CO and H2 occur with rich mixture

in airline use the engine's notorious large and bright violet-white exhaust plume alarmed some passengers