my first ramjet

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jimbob33
Posts: 7
Joined: Sat Dec 29, 2007 5:12 am

my first ramjet

Post by jimbob33 » Wed Jan 02, 2008 6:00 am

hi i'm new, but i've recently built a ramjet from 16 gauge mild steel. I used alot of ideas from the maggie muggs, and glenn olsen
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DSCN1754.JPG
the cones before final welding, sizes, diffuzer 1.5in entrance 3.0in exit 4in lenth, CC 3.0in dia. 4.5in lenth. nozzle 3in entrance 2.125in exit.
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final welding on body is done
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the inital design was changed for a removable flameholder design by cutting the diffuzer and part of the CC
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the mock up for the removable flameholder design, a ring of metal that slips over the CC.
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the finished design minus flameholder.
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stands are made.
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the finished stands.
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the flameholder (later modified), fits inside the ring on the diffuzer which butts up againist the CC.
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the finished product.
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the retention screws are installed
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love, peace and chicken grease.

jimbob33
Posts: 7
Joined: Sat Dec 29, 2007 5:12 am

Post by jimbob33 » Wed Jan 02, 2008 6:19 am

the rest. video coming soon.
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the fuel tube and needle valve.
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a different flame holder covers 30% CC cross area.
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ready to test.
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best run of the day
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love, peace and chicken grease.

larry cottrill
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Post by larry cottrill » Wed Jan 02, 2008 2:45 pm

jimbob -

Man, that is fabulous!

NICE JOB! Hope you can get the videos set up soon. What power is your blower, and what flow speed is claimed for it?

You nicely fixed the three greatest flaws in my original Maggie design: The suboptimal diffuser, the crude flameholder, and (of course) the glued construction. Looks like you ended up with something you can really be proud of!

Congratulations!

L Cottrill

jimbob33
Posts: 7
Joined: Sat Dec 29, 2007 5:12 am

Post by jimbob33 » Thu Jan 03, 2008 1:34 am

thanks larry, i'm using 250 mph electric blower but i have a speed control so i
have compleatly adjustable speed, so far i can only get up to less than half thottle before a flameout, i think i need more fuel, i have a propane regulator setup so i have as much pressure as i need, but my fuel orffice is only .056 in
but i also need to "port" the valve body out. also i am making a thrust cart as i speak.
love, peace and chicken grease.

jimbob33
Posts: 7
Joined: Sat Dec 29, 2007 5:12 am

Post by jimbob33 » Thu Jan 03, 2008 1:40 am

heres a vid
Attachments

[The extension wmv has been deactivated and can no longer be displayed.]

love, peace and chicken grease.

jimbob33
Posts: 7
Joined: Sat Dec 29, 2007 5:12 am

Post by jimbob33 » Fri Jan 04, 2008 1:55 am

today i tested my ramjet on my new thrust measuring cart, and THRUST!!!!!
at 20% thottle the engine slowly moved forward towards the blower. YES!!!
love, peace and chicken grease.

Bruno Ogorelec
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Post by Bruno Ogorelec » Fri Jan 04, 2008 6:43 am

jimbob33 wrote:today i tested my ramjet on my new thrust measuring cart, and THRUST!!!!!
at 20% thottle the engine slowly moved forward towards the blower. YES!!!
Congratulations! Yes, this is it! A true ramjet. Feels good, doesn't it? Looks nice, too. A very good effort.

larry cottrill
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Post by larry cottrill » Mon Jan 07, 2008 2:04 pm

Yes, very nice indeed! That's really a nice air source to have available.

Just curious: Why is there NOT sound on the video file? Every once in a while someone posts a silent video, and I'm never sure why this is the case.

A nice picture of your engine in action, though! With the air source you have, you might be able to do one even larger someday.

L Cottrill

jimbob33
Posts: 7
Joined: Sat Dec 29, 2007 5:12 am

Post by jimbob33 » Tue Jan 08, 2008 4:54 am

its a older digital camera so it has no sound but im working on geting one with sound.
love, peace and chicken grease.

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