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Posted: Mon Jun 25, 2012 2:04 am
by Petitlu
To do all these tests, I plan to make a Exterminator II.
there will be an opportunity to make a simple ignition, a multi-point and at any point of the chamber.
The fuel can also be injected at different locations.
the only problem being to put the fan ...

Posted: Mon Jun 25, 2012 11:05 am
by Petitlu
taser for ignition :
[youtube][/youtube]
Posted: Mon Jun 25, 2012 4:04 pm
by Petitlu
tests :
[youtube][/youtube]
Marx generator
Posted: Mon Jun 25, 2012 7:30 pm
by Technician1002
Watching the videos suggest a Marx Generator inside and the length of the chamber would be the ultimate ignition for a long multi gap spark strip.
http://en.wikipedia.org/wiki/Marx_generator

Posted: Tue Jun 26, 2012 12:26 am
by Petitlu
Yes I know!
and I thought to my future tests!
But we must make a ...
Posted: Tue Jun 26, 2012 2:52 am
by Petitlu
I modified the taser to be more practical.
I put a push button instead of the switch.
[youtube][/youtube]
Posted: Tue Jun 26, 2012 2:06 pm
by Petitlu
[youtube][/youtube]
Posted: Wed Jun 27, 2012 3:23 pm
by Petitlu
Today, with a test electrode multi point!

In one test, the piezo, the AGM and AGE were not triggering the explosion, I put the tazer and then .. boom at first!
You take a taser + a multi electrode point => TOP
[youtube]
[/youtube]
Posted: Wed Jun 27, 2012 3:55 pm
by Petitlu
Test with a central ignition and ignition system flash + transformer.
And a test gas with a lighter electronics
[youtube][/youtube]
Posted: Thu Jun 28, 2012 1:49 am
by jackssmirkingrevenge
VERY nice!
That looks like a
proper detonation, the high energy spark really makes a difference!
Excellent R&D work, keep it up

Posted: Thu Jun 28, 2012 2:11 am
by Petitlu
Thank you!
It is essential to have a good spark and the taser is excellent for that.
If I make a PAL, it will be multi-point!
By cons, multipoint ignition is really powerful if the fuel / oxidant is well done, if combustion is done in one place
Posted: Thu Jun 28, 2012 4:38 am
by jazzman56
Petitlu
Very very interesting of how the internal flame front acts with obstacles, the type of spark gaps and the where it is placed in relation to the chamber.
Is there any chance of getting a picture/schematic of your Flash And Transformer ignitor i am curious of how you achieve these better sparks.
Jazzman
Posted: Thu Jun 28, 2012 5:13 am
by Petitlu
Voici un schéma et une photo :
I replaced the push button by a 12v car relay, the black cube that you see in the picture.
Precision: the primary of the transformer connects to the capacitor and the secondary to the electrodes.

[/img]
Posted: Thu Jun 28, 2012 7:39 am
by DYI
That looks like a proper detonation, the high energy spark really makes a difference!
This is definitely NOT a detonation - the VoD in propane/air is roughly 1800m/s for a steady detonation (it goes faster as an overdriven detonation during the DDT process). Even if the chamber were two meters long, 1000fps filming would only capture it "in progress" for a single frame, if you were lucky.
Also, "high energy spark"? A 30g tetryl charge will not directly initiate detonation in unconfined propane air, and I'm guessing that Petitlu is dumping a lot less than 150kJ across that spark gap

I see nothing here to indicate either direct initiation or DDT.
Posted: Thu Jun 28, 2012 7:47 am
by Petitlu
For this reason JSR wrote "looks" and not "it's a detonation"
