24 replies to this topic

[davis f1_2002]

Who it be possible to build an Formula 1 engine without spark plugs and if so what would be the advantages and disadvantages? Could some form of catalyst be added to the fuel in the engine cylinder to lower the activation energy of the fuel or is that just a stupid idea.

[Pioneer]

Err not sure I understand the question.

Without spark plugs, whats going to ignite the fuel?
It doesn't just explode on its own.


Besides, if you could do away with spark plugs, you'd lose the capability of TC system to work by cutting spark.

[Limey]

I seem to recall that some model engines uses glow plugs instead of spark plugs to ignite the fuel.

[testarosa]

That’s how a diesel engine works. The fuel ignites itself. I don't see what the advantage would be, though.

[Roadkill]

Originally posted by testarosa
That’s how a diesel engine works. The fuel ignites itself. I don't see what the advantage would be, though.

Well,eliminating the attendant high voltage generating coils and timing devices would be an advantage no?

[desmo]

To the best of my knowledge, CI (compression ignition) four strokes are perfectly legal for F1. They aren't used primarily because they have lower specific power outputs than SI engines in naturally aspirated form, no?

[Pioneer]

Diesel's can do it because diesel fuel burns at a lower temperature than gasoline. They are a real bitch to get started when its cold though. Do those CI engines burn gasoline Desmo?

I don't see much of an advantage to getting rid of spark plugs. In fact I see advantages in that they can be electronically controlled, whereas in a CI engine, you would have no control over combustion.

[Limey]

That’s how a diesel engine works. The fuel ignites itself. I don't see what the advantage would be, though.

The glow plug isn't used previous to starting as in a diesel engine. On a model engine (as part of a model plane), a battery is attached to the glow plug, the engine started by flicking the propeller. The battery is disconnected and the glow plug stays hot enough because of the fuel combustion. These engines rev at 10 - 20,000 rpm. The compression ratio on these engines are less than diesel engines.

On a car engine, the plug would be electrically powered but the time for the glow plug to reach optimum temperature is infinately longer than a spark between two electrodes.

[david_martin]

One of the biiggest issues in taking the plug out of the combustion cycle with the FIA mandated fuel is the effect on the engine heat balance. F1 engines run very cold plugs, and the plug is actually a rather important heat dissipating element in the combustion chamber. With the combustion characteristics of modern gasoline, I really doubt it would be feasible.

[MRC]

Don't know that removing the plug would do anything for you except for maybe increasing the piston to plug clearance and force you to find another means of ignition.

While the spark plug removes heat, removing it and replacing it with combustion chamber wall would likely be sufficient, provided you have something else to ignite the charge.

quote: "Well,eliminating the attendant high voltage generating coils and timing devices would be an advantage no?"

Sure. Let's get rid of the pistons, too. They're heavy.

You do have something in a modern CI engine controlling your timing --- fuel injection timing. The fuel octane rule would be a non-issue. I believe that the rule likely states a maximum of octane number, not a minimum. Correct me if I am wrong on this. You want a low octane number (or high cetane number) to avoid knock in a diesel. You want the minimum ignition delay that you can get. The combustion is also not an explosion, per se, just because it is a diesel. Injection rate, fuel swirl, and air swirl will have an influence on the combustion.

As a friend suggested to me, TC could likely be accomplished with fuel. You could change the timing and/or reduce fuel injected.

As per the second question, if that catalyst would reduce the 0-10% burn time in CAD, then I would see that as being beneficial. Don't know if something like that would help in that way, though. Of course any benefits would have to outweigh any losses imposed in some other area, like air flow or something like that. Is that along the lines you were thinking of?

[UreaBorealis]

Originally posted by testarosa
That’s how a diesel engine works. The fuel ignites itself. I don't see what the advantage would be, though.

Faster burning of fuel?

I think I've read somewhere that in self-combustion the burning process is similar to explosion, hence the faster burning. I think that's why the sound of diesel engines is more "violent" than gasoline engines.

Am I anywhere near the truth? Finally my question: Would it be possible to build self-combustion engines using gasoline?

[AS110]

Getting rid of sparkplugs?

How about something like surface discharge plugs? Developed for CDI in outboards and bikes.But we do away with screw in plugs,and use two points in the combustion chamber for the spark to jump across.There is no heatrange to worry about,and as an F1 engine comes apart for it's 10,000km service,the contact bits can be changed at the same time.

Surface gap plugs were a brilliant idea,that like all things that will change the world,disappeared without a ripple.

[Oho]

Ave !!!

Regrading Diesel process:

http://www.qrg.ils.n...sel/diesel.html

and Otto process:

http://www.qrg.ils.n.../otto/otto.html

The other key difference besides the ignition type is the combustion. In Otto (gas) the combustion ideally takes place when piston is in its top dead center position, volume remains constant, while in Diesel the pressure in the combustion chamber remains constant, ie the gasses expand while burning when in Otto engine the pressure in the cylinder increases during combustion.

- Oho -

[random]

I recall that Mad Max (Mosley) did mention some time ago that Diesel motors had been suggested as a replacement once the current formula had run it's course. I suppose sometime after 2007.

Although, I'd rather see hybrid electric or hydrogen fuel cell vehicles with electric motor drive.

[Ali_G]

Originally posted by random
I recall that Mad Max (Mosley) did mention some time ago that Diesel motors had been suggested as a replacement once the current formula had run it's course. I suppose sometime after 2007.

Although, I'd rather see hybrid electric or hydrogen fuel cell vehicles with electric motor drive.

I get the feeling that f1 will (hopefully) never change from Petrol engines.

Who would want to see a Diesel engined car going around the track. Imagine the noise of the engines. It would be a disgrace.

I know that Fuel Cell's are the way forward, but I hope that f1 will always be the place where the Petrol Engine will be further developed.

Niall

[desmo]

To the best of my knowledge, "surface gap" plugs are standard in F1.

[MRC]

Surface plugs are usually employed to clear up room between the piston and plug, and are not neccesarily the best spark plug for a high power application. From my understanding, surface gap plugs offer more quenching area close to the spark kernel, and can slow kernel formation during intial stage.

Desmo, am I correct in assuming the use of surface gap plugs in F1 is due to the lack of clearance between plug and piston, in light of striving for higher compression ratio?

I remember seeing something in the mid ninties that was some research into a different approach to spark location. I believe it was Saab who was trying something that had a piston with a 'point' or 'nub' on the surface in the middle. That was one part of the electrode (presumably ground) and the other portion was the in the typical spark plug location. Don't know what the results were, but I imagine that the timing window was a big issue, along with the possibility of slowly pitting the rings.

UreaBorealis, try doing a search for HCCI (Homogenous Charge Compression Ignition) engines.

[JollyRoger]

Might sound a bit strange, but would it be possible to use the spark plugs to add energy to the combustion process, and increase the power created?

[Top Fuel F1]

Originally posted by davis f1_2002
Who it be possible to build an Formula 1 engine without spark plugs and if so what would be the advantages and disadvantages?

Some one already mentioned Diesel, so I'll have to come up with something different. Although outrageous you could invent a 4 cycle piston engine that burned Hypergolic fuel. When the the interacting hypergolic fuel comes in contact with it's oxidizer, they ignite on their own with no need for any other ignition source. This has been used in some liquid rockets. Instead of the contiuous burn in the rocket engine a pulsed injection (in step with the firing order of the engine) of the two chemicals would have to be devised.

The advantage could be that a very powerful engine could be the out come.

The disadvatage would be that these fuels are very dangaerous toxic agents. With some, just having your skin touch them (let alone breathe them) has very dire results. Can you imagine the pit stop for instance.

Better stick with the spark plugs!

[Top Fuel F1]

Originally posted by Top Fuel F1


Some one already mentioned Diesel, so I'll have to come up with something different. Although outrageous you could invent a 4 cycle piston engine that burned Hyperbolic fuel. When the two interacting hyperbolic fuels come together, they ignite on their own with no need for any other ignition source. This has been used in some liquid rockets. Instead of the contiuous burn in the rocket engine a pulsed injection (in step with the firing order of the engine) of the two chemicals would have to be devised.

The advantage could be that a very powerful engine could be the out come.

The disadvatage would be that these fuels are very dangaerous toxic agents. With some, just having your skin touch them (let alone breathe them) has very dire results. Can you imagine the pit stop for instance.

Better stick with the spark plugs!

Re:

http://poes.gsfc.nas...unchvehicle.pdf

I'm surprised no one caught this. The correct spelling is Hypergolic (of rocket fuel): Igniting spontaneously on contact with it's oxidizer.The (Re:) URL contains a PDF with info on the Titan II launch vehicle which used hypergolic fuel.

[desmo]

Yes MRC, my understanding is that the surface gap plugs are indeed a response to the CC geometries imposed and the quest to gain any incremental CR possible. Sorry about the late reply, my monitor died and I've just replaced it. I've been told that racing engines are in general fairly indifferent about the spark qualitatively as long as it has sufficient energy to initiate combustion in a timely matter. Ignition timing and heat range are more critical.

[MRC]

There seem to be two camps on spark quality and it's effect on engine output. One camp is of the opinion that a spark is a spark is spark is a spark. The other camp being that spark quality and plug configuration will effect things to a noticeable degree. With flame kernel formation and COV of IMEP (coeff. of variance) being effected. I must say that I used to be in the former camp, but have moved away and know am in the latter mentioned camp.

I think proper ignition timing is of paramount performance for maximum torque output and throttle response. With proper heat range being also of importance. I think that you can get something out of different plug configurations, but that this is of less importance, and more engine specific on whether any benefits will be gained. CDI and things such as smaller center electrodes can result in gains in some engines. Again, being to a large extent, application specific, in my opinion.

mark

[desmo]

It would be really interesting to see some good P/V (pressure/volume) loops of a test engine with varying spark ignition strategies. Has anyone published such a thing? I'd expect reductions in cycle to cycle variability might be a good place to look for results. I've obviously spoken with someone in camp one, but I think his point was that meaningful further gains through "better" sparks were unlikely to be found now given the current tech baseline.

[palmas]

I cannot see anyone making pressure detonation on the high octane fuel aloud! Also, if you can't control the detonation (and detonation point) you're loose lots of goodies, like traction control, adjusting torque curve, etc.

[Jaxs]

The spark plug is an essential part of the ignition system, the URL will help.....


http://www.ngksparkp...gs/techtips.asp

Rgds

Jaxs