Blast Compression Intake proposed design

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cadet
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Re: Blast Compression Intake proposed design

Post by cadet » Tue Jul 01, 2014 12:54 pm

I know this is an old thread but does anyone know the results of this engine?

Bruno Ogorelec
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Re: Blast Compression Intake proposed design

Post by Bruno Ogorelec » Tue Jul 01, 2014 1:14 pm

Yes. The short answer is there have been none. A long story would have a description of a British effort that yielded non-sustained series of something that looked like it would burst into life kicking and screaming any moment -- but never did.

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Re: Blast Compression Intake proposed design

Post by tufty » Tue Jul 01, 2014 4:47 pm

Hey Bruno! Good to see some of the old faces are still around.

How's things? Oddly, I was going to contact you last week. I don't suppose you have dimensions for the Ecrivisse, you you? I've got access to a workshop again, and fancy making something stupid in my lunch breaks; it occurred to me that the Ecrivisse has been talked about a lot, but nobody seems to have duplicated one.

Simon

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Re: Blast Compression Intake proposed design

Post by Bruno Ogorelec » Tue Jul 01, 2014 6:38 pm

Hello!

I've dug out a rough sketch of the Type B Ecrevisse with intake and exhaust thrust augmenters, with dimensions in milimeters.

I think I also have a sketch of another model. If I find it, I'll post it.

Good luck with the project.
Attachments
Ecrevisse B plan2.jpg

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Re: Blast Compression Intake proposed design

Post by Bruno Ogorelec » Tue Jul 01, 2014 6:46 pm

Here's the other one.

Both are really very rough. Sorry about that.
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Ecrevisse_dimensions_01.jpg

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Re: Blast Compression Intake proposed design

Post by tufty » Fri Jul 04, 2014 4:06 pm

Thanks Bruno, you're a star.

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Re: Blast Compression Intake proposed design

Post by Bruno Ogorelec » Mon Jul 14, 2014 11:15 am

Tufty, maybe you can acquire an original Ecrevisse. Take a look at this:
http://webcache.googleusercontent.com/s ... en&ct=clnk

The guys obviously do not care very much about the jet engine part. For them, the car's the thing.

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Re: Blast Compression Intake proposed design

Post by cadet » Mon Jul 14, 2014 4:27 pm

Thank you for your reply Bruno. I have a couple general hypothetical questions about a PDE if you have the time. Is there a safe minimum thickness of stainless steel to use for a PDE with a combustion chamber at about 4" diameter? Also is there a rough estimation of the difference in power generated from a deflaguration vs. a detonation?

Thanks again.
Cadet

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Re: Blast Compression Intake proposed design

Post by Bruno Ogorelec » Mon Jul 14, 2014 9:11 pm

cadet wrote:Thank you for your reply Bruno. I have a couple general hypothetical questions about a PDE if you have the time. Is there a safe minimum thickness of stainless steel to use for a PDE with a combustion chamber at about 4" diameter? Also is there a rough estimation of the difference in power generated from a deflaguration vs. a detonation?

Thanks again.
Cadet
I don't know much about PDEs. It's a rather arcane subject. The power impulses for the same engine volume are much much much more powerful than in the pulsejet. I don't really know how much stronger, but it beats any other internal combustion engine as far as I know.

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Re: Blast Compression Intake proposed design

Post by cadet » Tue Jul 15, 2014 4:58 pm

More research for me then. Thank you though. And speaking of research I would like to extend a heartfelt thank you to all the work you have done. Especially your historical review of pulsejets. I have read it many times and feel I learned more from that than any other single source.

My gratitude
Cadet

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Re: Blast Compression Intake proposed design

Post by Bruno Ogorelec » Tue Jul 15, 2014 5:21 pm

cadet wrote:More research for me then. Thank you though. And speaking of research I would like to extend a heartfelt thank you to all the work you have done. Especially your historical review of pulsejets. I have read it many times and feel I learned more from that than any other single source.

My gratitude
Cadet
Thank you for the kind words, Cadet! Glad you liked it. I'm afraid it's a bit out of date by now. And it does need a stronger scientific backing (more acoustics and thermodynamics). Unfortunately, I have never found anyone willing to cooperate on an update.

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Re: Blast Compression Intake proposed design

Post by tufty » Thu Jul 17, 2014 12:14 pm

Bruno Ogorelec wrote:Tufty, maybe you can acquire an original Ecrevisse.
Hah! Unfortunately, the engine is part of the car's history, and the price is "slightly" out of my reach.

Anyway, I was poking about looking for other documentation (particularly the Artt, Richardson & Blair 1984 paper, hint hint) and came across a few amusing tidbits:

This paper, for example references a good number of names familiar around here, and a few unknowns - apparently a chap named "Ogorolec" has done some work on pulsejets, can't say I've ever come across him.

And this one, from around your neck of the woods references Larry.

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Re: Blast Compression Intake proposed design

Post by Bruno Ogorelec » Thu Jul 17, 2014 3:05 pm

Hahahahaha, thanks, Tufty. An interesting paper. Wish we had the resources of those guys back then. Still, with all the resources at hand, including impressive computing power, they could not get their engine to sustain. :D Pulsejetting is still as much art as it is science and engineering. :D

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Re: Blast Compression Intake proposed design

Post by cadet » Thu Jul 17, 2014 4:41 pm

I would offer to help but I dont know enough to be of any assistance. I've been reading the forum for about 6 months now so any knowledge I have probably came from you or another forum member. Im more into building than theory. I believe I've learned enough to try to make one. Im a TIG welder by trade with machining skills. So with your research, and pyrojoes recipe for beginners im making a 9 blended body pulsejet. It should be done in a little less than a week. Sooner if I get more free time. It may or may not work but it is interesting and fun. Its been said many times to start with an easy known design but I'm stubborn. I will post pictures and videos when its done.


Cadet

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Re: Blast Compression Intake proposed design

Post by Mike Everman » Mon Jul 21, 2014 5:48 pm

Anyway, I was poking about looking for other documentation (particularly the Artt, Richardson & Blair 1984 paper, hint hint) and came across a few amusing tidbits:

Hi Simon,
I'm sending you that paper. Too big to post! Hope all is well.
Mike
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