The Myers engine

Viv · Post by **Viv** » Thu Nov 27, 2003 9:48 pm

This is a reminder of an engine originally found by Larry and posted on the old forum, By the way were are you Larry!

Looking through the Schmidt papers Andrew sent over (brilliant) I came across an image of the Argus works third prototype.

Apart from the valves this is very like the Myers engine in layout.

Both images are attached.

Viv

Bruno Ogorelec · Post by **Bruno Ogorelec** » Fri Nov 28, 2003 5:26 pm

Neat one, Viv! A good eye. But, Myers makes a point of the ring of spark plugs on the exit. Any thoughts on that?

Viv · Post by **Viv** » Sat Nov 29, 2003 12:25 am

brunoogorelec wrote:Neat one, Viv! A good eye. But, Myers makes a point of the ring of spark plugs on the exit. Any thoughts on that?

Smoke and mirrors old friend, after a bottle of pino grigio that is! one spark is as good as a whole load of them?

viv

Post by **Mike Everman** » Sat Nov 29, 2003 12:34 am

I worked with this geezer a long time ago that was rabid about the benefits of more sparks in IC engines. he was making heads with 6(!) plugs in each cylinder. i was in the middle of a string of short term postings, so I wonder what ever happened to his idea?

Bruce · Post by **Bruce** » Sat Nov 29, 2003 1:27 am

I don't see how multiple plugs would be a good idea -- possibly they'd even be a bad one, certainly in a conventional reciprocating piston engine.

The reason for this is that you don't want to encourage too rapid a combustion or you'll damage the engine. The idea is that the combustion should produce a rise in pressure, not the formation of shockwaves (pinging/pinking).

Lots of work goes into the design of cylinder-heads and piston crowns to try and ensure that the air/fuel burns at just the right rate over a wide range of operating conditions.

Those unfamiliar with such things should google for "squish band" see what just one element of the complex puzzle's all about.

Post by **Mike Everman** » Sat Nov 29, 2003 4:24 am

yeah, certainly not good to drive a high enertia thing (piston, etc.) with a detonation, hell on valves too. I think he was in to super lean engines and was still keeping it from detonating somehow. Like I said, I don't know if he was a crackpot or what. Good designer, though.

Mark · Post by **Mark** » Sat Nov 29, 2003 7:05 am

Mike Everman wrote:I worked with this geezer a long time ago that was rabid about the benefits of more sparks in IC engines. he was making heads with 6(!) plugs in each cylinder. i was in the middle of a string of short term postings, so I wonder what ever happened to his idea?

If you build an engine with 2 large spark plugs on opposite sides of the combustion chamber, you could use the base of the plugs as a way to mount or hold the jet in a test stand easily. And too, you can just attach the two leads to the tips of both plugs which is kind of fancy.
Anyway what I was wondering about is how to drive a bank of spark plugs, say a dozen all at once, without electricity playing tricks and taking the shortest path leaving some out of the game?
Also in a very long tube it might be of some benefit in some design to initiate/propagate ignition from both ends of the duct at the same time. This might elicite some new characteristics or allow something new to evolve.
Mark
Mark

Mark · Post by **Mark** » Sat Nov 29, 2003 9:14 am

Mike Everman wrote:I worked with this geezer a long time ago that was rabid about the benefits of more sparks in IC engines. he was making heads with 6(!) plugs in each cylinder. i was in the middle of a string of short term postings, so I wonder what ever happened to his idea?

I can't remember the specifics, but in dragsters they dump a huge amount of amps into the cylinders, a kind of heat injection, and nearly pure nitromethane for fuel. After too many detonations, they blended in a small fraction of methanol to prevent that effect.
And then too I remember something about how the "spark plugs" are consumed in the process, eaten in short order. Perhaps they should be called arc plugs.
Zero to 300 in short order.
Mark

Bruno Ogorelec · Post by **Bruno Ogorelec** » Sat Nov 29, 2003 5:57 pm

In piston engines, multiple plugs may be a bad idea, though many racing engines worked very well with twin plugs. Today, Alfa Romeo uses twin plugs on some of their road engines. In a pulsejet, I don't know. It's a different story. You want to get as close to detonation as possible.

Bruno

Viv · Post by **Viv** » Sun Nov 30, 2003 10:25 pm

Flame speed is the issue in some engines, if the bore size is large and the combustion chamber is hemipherical the flame path can be significantly long.

Two spark plugs will give a shorter flame progression time aka the Alpha Romeo twin spark and a number of other engines.

The myers engine on the other hand was a I believe trying to get a good start to a planer flame front from the multiple spark plugs.

Viv