Honda Power Unit Hardware & Software

[Craigy]

Mr. Potato Head (Patrick Head maybe? ). What about heating fuel in the combustion chamber with microwaves? One of the guys mentioned heating fuel is essential to TJI. However, is it necessary to heat all the fuel entering the chamber or just part of it? Microwaves could provide this additional control during the heating process.

Packaging six exciters (magnetrons) into the headspace would be quite tricky. Wouldn't directly heating the fuel with an element in/around the fuel rails (before it's injected) be much easier?

[godlameroso]

Or the pre-chamber itself has a heating/vaporizing element. I mentioned microwaves for fuel heating(magnetrons can be made very compact) but as far as I'm aware gasoline isn't a polar molecule. In any case there's a decent amount of heat sources in the ICE that could serve the same purpose. Maybe a hot ring made of platinum or iridium in the pre-chamber to help vaporize the fuel. I'd imagine it would be hard to inject fuel that was vaporized before the pre or main chamber even in a supercritical state.

[MrPotatoHead]

Mr. Potato Head (Patrick Head maybe? ). What about heating fuel in the combustion chamber with microwaves? One of the guys mentioned heating fuel is essential to TJI. However, is it necessary to heat all the fuel entering the chamber or just part of it? Microwaves could provide this additional control during the heating process.

Growing up I always had a lot of admiration and respect for Patrick Head

The idea of pre heating fuel is not new to Honda. They did it with the Toluene back in the last turbo F1 era.

[MrPotatoHead]

Or the pre-chamber itself has a heating/vaporizing element. I mentioned microwaves for fuel heating(magnetrons can be made very compact) but as far as I'm aware gasoline isn't a polar molecule. In any case there's a decent amount of heat sources in the ICE that could serve the same purpose. Maybe a hot ring made of platinum or iridium in the pre-chamber to help vaporize the fuel. I'd imagine it would be hard to inject fuel that was vaporized before the pre or main chamber even in a supercritical state.

Would that not pose a potential hot spot that could cause pre-ignition? Not discounting the idea - just asking what you think

And no i do not believe you can heat petroleum with microwaves.

[mrluke]

If you wanted to pre-heat fuel why dont you put say the intercooler in the fuel tank to both cool charge and heat fuel.

[etusch]

If you wanted to pre-heat fuel why dont you put say the intercooler in the fuel tank to both cool charge and heat fuel.

I don't know what kind of benefits in heating fuel. But I know in cold wethers engines works better. Of course this is because of more oxijen in same volume than heat wethers. Cold air and hot fuel is better ?

[Vortex37]

Rather than me writing a long argument about indirect chambers. Let me point the technical people who are still viewing, to the work of Dr Dan Merritt [UK] and his lean burn technology. This is something I came across in 1988. If you take the time to read his notes, you will probably have a different view on the indirect chamber and what topology to select. Highly atomised fuel drops do not need to be spread out in the pre-chamber. In fact it is a disadvantage. My screen name was chosen to reflect my thoughts, about tumble and stratification. The latest Patents on the TJI principle look at intense swirl in a chamber that is very different to anything seen or suggested here. This also links into what might be a good main chamber topology - Excess air and keeping fuel away from cylinder walls. Merritt shows a method of creating a vortex swirl via a 'ramp shape', and the results. There was much discussion, back in the sensible days of the main thread, about stratification, and I think that a vortex injection from the pre-chamber is a better way to this end. The 'hose pipe' method seems intuitively wrong. The other issue is the problem of increased efficiency leading to lower exhaust temps and the effect on MGU-H/Turbo - change the pre-chamber/main chamber then affect downstream - reprogram and back to the beginning again. Thinking that just changing a few castings and off we go in a few weeks, is cloud cuckoo land for Honda or anybody.

Whilst the web link is substantially about lower emissions and improved fuel consumption, there are some lessons to be had.

https://www.pureburnengines.co.uk

Tumble is often used in intake port designs. I've personally made some intake port designs based around tumble because of some of the benefits it can bring. It helps a lot at part load especially.

But - I sense a lot of snake oil on that website. No offense.
Reading that reminds me of the super lean carborators or dimples like a golf ball inside intake ports (don't get me started on the dimples. Please)
If they all worked as advertised then people would have been using them for years.

Oh and you very much can make changes to designs and be testing new heads in weeks not months. Maybe not at Honda though.
I'll be at a shop in a few weeks working on a new billet cylinder head project (not F1). I'll see what pics I can share if any while I'm there.

I am talking about tumble/swirl in the main chamber.

You are absolutely correct to say that you could produce a new head in a few weeks. But the point I addressed was that of an instant answer to Honda problems, which was your answer to somebody else. Any change might invite changes to Turbo/injectors/ignition/piston/valve topology etc. Not forgetting all the programming that seems to be causing Honda and Renault so many problems.

Snake Oil? Well I'll leave you to judge. The independent data is all there. It's a road engine with different objectives!

[MrPotatoHead]

Tumble is often used in intake port designs. I've personally made some intake port designs based around tumble because of some of the benefits it can bring. It helps a lot at part load especially.

But - I sense a lot of snake oil on that website. No offense.
Reading that reminds me of the super lean carborators or dimples like a golf ball inside intake ports (don't get me started on the dimples. Please)
If they all worked as advertised then people would have been using them for years.

Oh and you very much can make changes to designs and be testing new heads in weeks not months. Maybe not at Honda though.
I'll be at a shop in a few weeks working on a new billet cylinder head project (not F1). I'll see what pics I can share if any while I'm there.

I am talking about tumble/swirl in the main chamber.

You are absolutely correct to say that you could produce a new head in a few weeks. But the point I addressed was that of an instant answer to Honda problems, which was your answer to somebody else. Any change might invite changes to Turbo/injectors/ignition/piston/valve topology etc. Not forgetting all the programming that seems to be causing Honda and Renault so many problems.

Snake Oil? Well I'll leave you to judge. The independent data is all there. It's a road engine with different objectives!

I was also talking about tumble in the chamber as well.
The design of the intake port and the path it takes can greatly induce and affect the tumble / swirl of the air inside the cylinder.
This is especially seen in many diesel cylinder heads. In fact often when people port a diesel head they think that removing the apparent shapes and obstructions in the intake port will help create more power - when often the result is less power because of less swirl in the cylinder.

And i do agree that obviously quick turnaround on parts depends on knowing the answers or what to change and that could have knock on effects on other parts of the engine.
We also do not know their supply chain. How much do they machine in house vs someone doing outside? This can create huge delays when you depend on others.

And yes I may have been overly harsh with my snake oil comment - but as far as it's use or potential use in F1 that would be some very snakey oil

[godlameroso]

Or the pre-chamber itself has a heating/vaporizing element. I mentioned microwaves for fuel heating(magnetrons can be made very compact) but as far as I'm aware gasoline isn't a polar molecule. In any case there's a decent amount of heat sources in the ICE that could serve the same purpose. Maybe a hot ring made of platinum or iridium in the pre-chamber to help vaporize the fuel. I'd imagine it would be hard to inject fuel that was vaporized before the pre or main chamber even in a supercritical state.

Would that not pose a potential hot spot that could cause pre-ignition? Not discounting the idea - just asking what you think

And no i do not believe you can heat petroleum with microwaves.

I guess it depends on the pressures involved, gas behaves much like water in the sense that if you pressurize it, it's boiling point increases. @500 bar I imagine it takes quite a bit of heat to boil it, although when you inject the fuel it's pressure suddenly drops and actually cools for an instant. So I guess hot spots would be avoided with proper fuel heating, because when the fuel injection temperature drops, even for that split second before the endothermic reaction, you get some inevitable fuel condensation and wall wetting, which is the best way to increase combustion inefficiency.

[godlameroso]

If you wanted to pre-heat fuel why dont you put say the intercooler in the fuel tank to both cool charge and heat fuel.

I don't know what kind of benefits in heating fuel. But I know in cold wethers engines works better. Of course this is because of more oxijen in same volume than heat wethers. Cold air and hot fuel is better ?

When fuel burns it can't do so in a liquid state, it has to evaporate first. The warmer the fuel the easier it is to evaporate, the faster the fuel evaporates the faster the combustion. Ideally you want to inject fuel vapors and air and not in a liquid state as is done with injectors. Injectors inject fuel at pressure, when you lower the pressure of a fluid it's temperature drops, not to mention the entire combustion process has both an endothermic and exothermic component. So even though injectors can spray very fine mist droplets and the engine temperature causes it to quickly evaporate, there is still a small amount of condensation. Getting rid of that would help, and is probably the main take away message of that engine article.

[etusch]

Thanks

[gruntguru]

Or the pre-chamber itself has a heating/vaporizing element. I mentioned microwaves for fuel heating(magnetrons can be made very compact) but as far as I'm aware gasoline isn't a polar molecule. In any case there's a decent amount of heat sources in the ICE that could serve the same purpose. Maybe a hot ring made of platinum or iridium in the pre-chamber to help vaporize the fuel. I'd imagine it would be hard to inject fuel that was vaporized before the pre or main chamber even in a supercritical state.

And no i do not believe you can heat petroleum with microwaves.

Easy to test - in your own kitchen!

[MrPotatoHead]

Or the pre-chamber itself has a heating/vaporizing element. I mentioned microwaves for fuel heating(magnetrons can be made very compact) but as far as I'm aware gasoline isn't a polar molecule. In any case there's a decent amount of heat sources in the ICE that could serve the same purpose. Maybe a hot ring made of platinum or iridium in the pre-chamber to help vaporize the fuel. I'd imagine it would be hard to inject fuel that was vaporized before the pre or main chamber even in a supercritical state.

And no i do not believe you can heat petroleum with microwaves.

Easy to test - in your own kitchen!

Hahahaha. Thaaaaaanks

[gruntguru]

A wild idea - what if the Pre-Chamber was purged on the compression stroke by a passageway that went to the valve seat and was opened when the intake valve opened.
Or a passageway that was opened to the intake port by an element of a pre-chamber mounted fuel injector.

In either case compressed air from the intake port would force a purge and fill of the pre chamber.

You would need to choose a point in the cycle when the cylinder pressure is lower than the intake pressure ie intake stroke. In the end, what does this achieve? A reduction in residuals in the pre-chamber from <<10% to approximately 0%?

[3jawchuck]

Or the pre-chamber itself has a heating/vaporizing element. I mentioned microwaves for fuel heating(magnetrons can be made very compact) but as far as I'm aware gasoline isn't a polar molecule. In any case there's a decent amount of heat sources in the ICE that could serve the same purpose. Maybe a hot ring made of platinum or iridium in the pre-chamber to help vaporize the fuel. I'd imagine it would be hard to inject fuel that was vaporized before the pre or main chamber even in a supercritical state.

At least ethanol is a polar molecule, as for other components, I don't have a clue.