How to Calculate No of Sparks Produced in a SI Engine?

Depends on the number of cylinders and the type of engine (4-stroke, 2-stroke, Wankel).

What class are you taking?

Speaking of different types of engines, who was that guy developing a different type of IC engine that had some threads here on CR4? I did a search and came up short.

If I recall, it was a few years ago and he was well into prototyping at that point.

Anyone remember, or know where he's currently at, progress-wise?

ADoyle 88

http://doylerotary.com

Yep, that was it... thanks! Too bad it looks like there has been little activity for the past few years.

What is SI? (Never mind; I looked.)

Sparks/min = rpm x number of cylinders / number of strokes.

Unless of course it is a dual ignition/twin spark engine.

Isn't two strokes one rpm.

Correct!

A 4-stroke engine only makes 2 RPM for each spark.

So, Tornado is off by a factor of 2.

Why do I feel we just answered someone's homework question?

because we just did answer someone's homework... AGAIN!!

Two-stroke means one down stroke and one up stroke.

Someone gave you an off topic. All that shows is that he, like many others, does not understand the internal combustion engine. I would give you a GA if I knew how.

I know a little bit about engines.

There's been a lot of misinformation presented here.

adfalenski is not without fault here.

His comment does not give any indication of spark plug firing.

What he does say though, is that two stroke means 1 up and one down (for a vertical engine), and he is dead right but was given an off topic for it. His comment was in reply to a lot of codswobble.

Granted, in a literal sense.

My point is that his comment makes no reference to, "number of sparks produced in si engine", per revolution or otherwise.

You are right, in a literal sense. But the implication was that there is one power stroke per revolution in a 2 stroke and, therefore, 1 spark per revolution. You are correct, he didn't say it, but it was definitely not off topic.

OK. How's that?

Oops. That's what I get for staying up too late....

Tell me, Tell me......

GA by the way!!

<<SI

It also depends on if the engine is a two-stroke or a four-stroke engine. If it is a four-stroke engine, divide the result of the formula above by two.

It will also depend on how long this engine runs at 4000 RPM.

GA for this week's best graphic.

"Suck, squeeze, bang, blow"!

Or 'Suck Bang Blow' when I lived in Murrells Inlet, SC... great place during Bike Week... lived right down the street at the International GC, but this was when SBB was at the corner of 17 and 801... it has since moved.

Ummmm, in some cases, like older four cylinder Hondas, there were two coils. Each coil fired once every revolution. So in this case, there were four sparks per revolution. Of course, half of those sparks occured in cylinders on their exhaust stroke. Half were 'duds'.

Yep, the idea was to ignite any/all unburned fuel left in the cylinder during the exhaust stroke for improved pollution control. A simple system that actually worked well as the Accords in those days breathed very efficiently allowing excellent performance and gas mileage.

No, not really. This was really about only wanting to use two ignition coils instead of four and only two sets of points because there were no spark distributors on the motorcycle engines. I should have specified Honda motorcycles. My bad.

Strange:

Honda two stroke fuel injected:

A year ago you said, "I HAVE JUST COMPLETED MY B.TECH DEGREE IN MECHANICAL ENGINEERING".

What have you learned?

That the internet is the fountain of knowledge.

So he cast his net into its murky waters, then drank deep, and got encephalitis of the mind from the resulting sewage.

Yes, casting an inferior net into polluted waters can do that.

Firing Order of Cylinders (Automobile)

On most single cylinder engines it is 1-1-1-1-1-1-1-1-1-1-1-1.

111111--------111---11---11----111---11---11--11---111--

OK, What is this?

A fouling plug or bad magneto.

It is from an old "hit and miss" engine. Like the Bovaird and Fang seen here; http://cr4.globalspec.com/comment/1108899/Re-What-Is-It

In a V8 it is 4/rev unless;-

http://www.hemmings.com/hmn/stories/2008/04/01/hmn_feature26.html

Jim

Evinrude made a two stroke V8. It would have 8 sparks per revolution.

I can safely say, based on the reaction of my friend, to backing into the spark plug projecting from the two stroke engine on his go-kart, due to his hurried attempt to just-drive-it without-the-seatback-for-now, causing involuntary muscle reaction and a leap from the machine at speed, there where several sparks involved. I estimate this event took place at approximately 4000 rpm.

Would a jet turbine engine ignition be Spark Induced?

To calculate no sparks, just multiply by zero!

The firing order of the Dazist Allis tractor engine (used gunpowder)was

3-1-2-0-2-1-3-0-2-3-1-0-0-0-3-3-3-0-2-2-2-0-2-2-2-0-1-1-1-0 then cylinder 4 was brought in operation and another became the fallow cylinder

(From the Owner Operators Manual written by Roger Welsch)

Number of sparks is easy to find.

It is always one hundred!

The hard part is to find out in what time interval it happens.

They are designed to produce power on a rotating shaft. If sparks are wanted instead, try a bonfire.