WarrenW

Anyone know anything about laser spark plugs? I like the idea but I'm not gonna be the first one to test them on my S2k unless someone guarantees me in writing they'll buy me a new engine if these ruin mine. Laser Spark Plugs Could Cut Auto Emissions

BALTIMORE (AP) — Laser spark plugs could help cut emissions from your car.

That’s what Japanese researchers say, and they plan to discuss their new laser spark plug system Monday at an Optical Society conference in Baltimore.

Lasers strong enough to use as spark plugs have been too big to fit under a car hood until recently. But the researchers say they are now small enough to screw in like conventional spark plugs.

Laser spark plugs are more powerful, so they don’t need as much fuel to create the explosion that pushes the pistons inside engines. The lasers can also be aimed at the center of cylinder, not the top where current spark plugs sit, further increasing efficiency. And laser spark plugs can be made inexpensively from ceramics.

NuncoStr8

Sounds like someone doesn't understand how spark plugs work. They are located in the top of the cylinder because if they were in the middle the moving piston would run into them. When the piston is at the top of it's travel, the spark is actually in the middle of the combustion chamber. And can a company really mass produce what would be required for these laser igniters for less than the cost of a spark plug?

As far as reducing emissions, I'm seriously sceptical. Nitrogen and oxygen combine under the pressure and heat of combustion. If there was less oxygen left after combustion, there would be less nitrogen oxides, but reducing fuel to create a lean condition also causes the metals inside the combustion chamber to be consumed. A laser won't change that. It'll just chew up the laser instead of the spark plug. Not to mention that platinum plugs facilitate the combustion process. Are they proposing building the laser plug out of platinum?

As far as burning "more air and less fuel," you can show on a dyno that running leaner makes more power. But it is damaging to engines, not just spark plugs. The limiting factors with air-fuel ratios is not the spark plug.

Gasoline engines with multiple spark plugs to broaden the flame front have been produced before, and multiple sparks per combustion event is common. Indexing spark plugs to minimize the shrouding effect is a very old technique for increasing efficiency. It sounds like these people are using "laser" as a magic word intended to suspend disbelief in the absence of any data from real world applications supporting their claims.

IMHO, the claims are theoretical at best. Cool that it can be done, but offers zero practical benefit over existing technology. And the premise that leads to claims of increased efficiency are based on poorly understood concepts by people who are optical and material science engineers, not internal combustion specialists. But I could imagine there are certain cases where the laser igniter would deliver a practical benefit, perhaps replacing diesel glow plugs or for specific engine design and use cases.

bloodzombie

Sounds like you know about spark plugs, but maybe not enough about lasers.

http://reviews.cnet.com/8301-13746_7-10288476-48.html

There are already working prototypes and Ford will be putting it in production cars over the next couple years.

Penforhire

Very cool! Seems like they'll be able to achieve a more uniform and controlled flame front. No idea how much improvement that'll actually make but you have to like the idea. Wonder how the lens is kept clear enough of carbon build up? Seems like any light frequency that would be absorbed by gas fumes would also be absorbed by carbon, unless the beam is strong enough to vaporize build up.

Mr.E.G.

That doesn't change much of what Nunco said. I will add that there could be some theoretical benefits in the sense that the spark plug currently intrudes into the combustion chamber and it's housing obviously has some effect on the flow of gasses in the chamber. With a laser's ability to be focused at some finite point in space while it originates at some remove, that could allow for better combustion chamber designs as you could have just a tiny orifice at the top or even the side of the combustion chamber and the laser can be focused in the middle of the chamber without actually protruding into it (Just think of those paperweights they sell that are a glass cube with a pattern etched INSIDE the glass. This is made by focusing a laser at some coordinate in the middle of the glass without disturbing the rest of the material).

Additionally, if you had a sophisticated enough system, you could have multiple lasers or one laser that could be made to scatter and ignite multiple points in the mixture or maybe even have multiple bites at the same apple by way of monitoring the combustion event and then zapping it again if the bun was not complete enough. Combustion happens quickly but a sophisticated laser system could perform 1,000 cycles or events in this same amount of time.

Having said all of that, I agree with Nunco that this is probably snake oil and that the purported benefits per that quoted explanation sounds like someone talking out there ass.

Mr.E.G.

Goddammit. I guess I could have actually read your link which said (much more eloquently) everything I was trying to say. Doh!

ltswb

Well then, if Ford is pioneering it then it must be a reliable, fuel efficient, cutting edge technology, since that is what they are known for.

CNET isn't exactly a gear head site either. I'm curius what a real car site has to say. The phrase "ignite deeper in the cylinder" from the article has me curious. At compression the cylinder isn't exactly what I would call deep. I'm curious what the actual difference is, if there is any. Or if Ford is researching it because they got grant money from the government that stipulated that they research fuel efficiency tech.

Saki GT

I'd imagine keeping laser optics clean and aligned in a cylinder might be difficult...

Slithr

I suspect that they are really talking about more deeply into the combustion chamber as opposed to the cylinder. I guess in theory it would be possible to more precisely tune the ignition point for optimal flame travel. Also would allow for larger and perhaps more strategically placed valves, etc., as mentioned. Internal combustion engines are going to be with us for a while. If we can make them more fuel efficient, why not?

NuncoStr8

That article you linked is almost 2 years old already. According to the article, this was a working system that was a slam dunk for production cars over the "next couple years." Where is it? The "next couple years" have gone by already.

Companies, and people, research all kinds of things. That doesn't mean the things they research automatically become practical and beneficial. Anyone have a ceramic engine block in their car? At one time that was claimed to be the technology of the future, but after much research, was proven impractical. There are numerous similar examples.