Melting pistons.

[Accelerator]

Originally Posted by Fingers

That isn't exactly true....

Atomized fuel does not burn. It must vaporize first. The state change cools the fuel and the area around it and displaces any O2 within the plume. So the first stage of the injection event is a fuel fog as the leading edge of the fuel state changes. This takes real time, and propogates the plume towards the walls/piston.

The next phase has the vapors coming up to auto-ignition temp. This happens much faster, but still takes real time. But you still don't have ignition. You get some mixing of the air and the vapors here.

Finally, the vapors are up to temp and burn. The added heat back propogates through the plume and quickens the state change of the fuel fog. It also consumes the O2 at the plume boundry. Still, it takes real time for the fog to change state. BUT it is only burning on the border between the plume and the cylinder air. At this stage it resembles a candle flame with its layers.

Knock happens when you get your whole pulse in prior to the leading edge firering. Basically, the whole chamber is filled with fog that lights all at once. Almost like a gasser.

Burst is when you have managed to cool the chamber below auto-ignition temps. Call it a dead load.


But, what do I know......

Great detail, thanks!

[McRat]

Originally Posted by Fingers

That isn't exactly true....

Atomized fuel does not burn. It must vaporize first. The state change cools the fuel and the area around it and displaces any O2 within the plume. So the first stage of the injection event is a fuel fog as the leading edge of the fuel state changes. This takes real time, and propogates the plume towards the walls/piston.

The next phase has the vapors coming up to auto-ignition temp. This happens much faster, but still takes real time. But you still don't have ignition. You get some mixing of the air and the vapors here.

Finally, the vapors are up to temp and burn. The added heat back propogates through the plume and quickens the state change of the fuel fog. It also consumes the O2 at the plume boundry. Still, it takes real time for the fog to change state. BUT it is only burning on the border between the plume and the cylinder air. At this stage it resembles a candle flame with its layers.

Knock happens when you get your whole pulse in prior to the leading edge firering. Basically, the whole chamber is filled with fog that lights all at once. Almost like a gasser.

Burst is when you have managed to cool the chamber below auto-ignition temps. Call it a dead load.


But, what do I know......

Yeah, I know liquids don't burn. I think I've posted that before.

There is a video on the internet somewhere with a high-speed camera using a glass window to record the ignition event. The fuel ignites well before it hit the cylinder wall in that video. Not sure how many microseconds it takes to ignite.

The fuel burns as it's being injected. When it does not, bad things happen. If it takes a few microseconds to ignite, it still is igniting. Kinda like saying a match doesn't ignite when you strike it. Yeah, there is a delay, but it's not significant.

You can inject fuel ATDC and it will burn, even though the temperature is falling, not rising, just as long as the air is still hot enough. Look at a stock timing table. Going by the "delay theory", a Duramax would not idle.

[Accelerator]

Originally Posted by McRat

Yeah, I know liquids don't burn. I think I've posted that before.

There is a video on the internet somewhere with a high-speed camera using a glass window to record the ignition event. The fuel ignites well before it hit the cylinder wall in that video. Not sure how many microseconds it takes to ignite.

The fuel burns as it's being injected. When it does not, bad things happen. If it takes a few microseconds to ignite, it still is igniting. Kinda like saying a match doesn't ignite when you strike it. Yeah, there is a delay, but it's not significant.

You can inject fuel ATDC and it will burn, even though the temperature is falling, not rising, just as long as the air is still hot enough. Look at a stock timing table. Going by the "delay theory", a Duramax would not idle.

are you sure it's not a gas engine video pat?

[Accelerator]

Yep gas engine, enjoy!

http://videos.streetfire.net/video/I...a-4_167739.htm

[Accelerator]

cylinder head design..http://www.howcast.com/videos/7915-C...r-Head-Designs

[Accelerator]

http://www.gvsmedia.com/video-2/K9Zk...bustion-theory

Here kitty kitty

[McRat]

The one I'm think of is a diesel, but it's been years since I saw it.

Why don't you just tell us what your video links are about? Just in case you accidently cross-linked it with your gay porn site.

Not all the readers here have high-speed internet, so asking someone to watch videos to understand your post might take them hours.

[Fingers]

Originally Posted by McRat

Yeah, I know liquids don't burn. I think I've posted that before.

There is a video on the internet somewhere with a high-speed camera using a glass window to record the ignition event. The fuel ignites well before it hit the cylinder wall in that video. Not sure how many microseconds it takes to ignite.

The fuel burns as it's being injected. When it does not, bad things happen. If it takes a few microseconds to ignite, it still is igniting. Kinda like saying a match doesn't ignite when you strike it. Yeah, there is a delay, but it's not significant.

You can inject fuel ATDC and it will burn, even though the temperature is falling, not rising, just as long as the air is still hot enough. Look at a stock timing table. Going by the "delay theory", a Duramax would not idle.

I don't want to get in a pissing match, but the delays are significant. Here is a plot at/near idle. Cold chamber, but not a stone cold engine.



Point is, the injection delay is real, significant, and must be accounted for when tuning. I can pull a dozen plots to show how it varies with boost, ECT, RPM, rail pressure and timing. Does anyone really care? Probably not.

As always....What do I know?

[Fingers]

Here is the link to the Youtube video. It even shows the fuel streams prior to ignition.

[Accelerator]

Originally Posted by McRat

The one I'm think of is a diesel, but it's been years since I saw it.

Why don't you just tell us what your video links are about? Just in case you accidently cross-linked it with your gay porn site.

Not all the readers here have high-speed internet, so asking someone to watch videos to understand your post might take them hours.

this one is for you!
http://www.youtube.com/watch?v=FwNwb...eature=related

You guys want to learn, well here you go.

[Accelerator]

Originally Posted by Fingers

I don't want to get in a pissing match, but the delays are significant. Here is a plot at/near idle. Cold chamber, but not a stone cold engine.



Point is, the injection delay is real, significant, and must be accounted for when tuning. I can pull a dozen plots to show how it varies with boost, ECT, RPM, rail pressure and timing. Does anyone really care? Probably not.

As always....What do I know?

John, are talking about injection ignition delay? or just injection delay? Both have there validity here.

[Mike]

Originally Posted by Accelerator

this one is for you!
http://www.youtube.com/watch?v=FwNwb...eature=related

You guys want to learn, well here you go.

Where is the smiley for banging head against wall. Looks like you need to watch the video.

You mean this one?


edit

[Mike]

Originally Posted by Accelerator

John, are talking about injection ignition delay? or just injection delay? Both have there validity here.

Explain the difference would you?

[Accelerator]

Originally Posted by Mike

Where is the smiley for banging head against wall. Looks like you need to watch the video.

Touché

[Accelerator]

Originally Posted by Mike

Explain the difference would you?

Do i have to SPELL it out for you?

You know the difference mike!