"Thunderchine" 55 lb thrust pulsejet plans

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milisavljevic
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"Thunderchine" 55 lb thrust pulsejet plans

Post by milisavljevic » Fri Feb 13, 2009 4:30 pm

Greetings Everybody--

I am very pleased to present the forum with a new pulsejet specifically designed as an alternative
to the "classic" Lockwood-Hiller 55 lbf (245 N) valveless pulsejet. Until now, the only choices when
it came to pulsejets powerful enough for go-karts and other forms of "kinetic art" were either the
Lockwood or the more efficient, but less powerful 45 lbf (200 N) quad-intake "Kentfield" valveless.

No longer. Now you can have more thrust and higher efficiency combined into one compact motor:
thunderchine-steel-4in1.png
The Thunderchine's pulsejet "core" (shown below) is only 51 inches long (1295 mm); the Lockwood
is 104.25 inches long (2648 mm). With its u-bend a Lockwood folds down to 50 inches (1270 mm),
so the Thunderchine is only 2% longer (so sue me :wink: ). Thunderchine displaces 20 liters of volume
to the Lockwood's 25; if built from 0.5 mm stainless (ca. 25 gauge), Thunderchine's pulsejet core
tops a thrust-to-weight ratio of 10:1, easily besting the equivalent Lockwood (7:1). With respect
to fuel efficiency, Thunderchine's integrated ejector-augmentors allow it to be competitive with
the notably thrifty Kentfield and far superior to the Lockwood. Obviously, including the ejectors in
the mix means that Thunderchine develops more than 55 lbf of thrust. Estimated static thrust, at
sea level, is 63 lbf (280 N); for go-kart / propulsive uses, thrust increases with increasing speed.
thunderchine-core-isometric.png
I want to express many thanks to "Rossco", my innovative and tireless associate in this endeavor;
without his help, you would only have my poor MS Paint line drawings and no sheet metal patterns
to work from. Rossco helped me solve several practical problems ("how to dos"); my thanks, mate! :D

The attached plans are in the ubiquitous *.pdf format, so everyone should be able to open them
and print out the sheet metal patterns. Please note the default page size is A4 -- you can change
this, and that the actual patterns are very large; these must be printed out across multiple pages.
thunderchine-plans-1.zip
Please read these plans carefully: there are many notes covering all aspects of construction inside.

I will also point out that the plans do not include any fuel delivery system: there are many threads
on this site with helpful suggestions and advice; ask away if you do not know where/how to begin.

No fuel delivery system is included in part because the Thunderchine has been designed to run off
multiple fuels without significant modifications. Propane (vapour or liquid), gasoline (petrol), any
kerosene-based fuel (eg., Jet-A) and diesel are all equally acceptable. See the plans for more info.

Additional posts may follow with revisions, as needed, and I am always available to assist builders.

Enjoy!
M.
no safe haven for merchant scum


for ye merchants who do the prop'r t'ing only if
ye be haul'd-up on charges b'fore ye ship-mates
an' threat'nd wit' forfeiture of all ye precious loot
hear this - so-called stand-up guys YE BE NOT

avast!
Cap'n M.

phonedzero
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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by phonedzero » Fri Feb 13, 2009 5:17 pm

Sweet mother of Mary! I am going to go and price out stainless sheet today! What a beautiful engine!

metiz
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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by metiz » Fri Feb 13, 2009 5:37 pm

Quite an engine you got there, nice work. Why does the tail consist of multiple cones and not a straight pipe with a tailexpansion or just a single tail expansion without any straight pipe? additionally, is there a particular reason why there is no straight tail pipe section?

Regardless - beautifull engine guys, good work!
Video? :P
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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by larry cottrill » Fri Feb 13, 2009 5:55 pm

Mssr. M -

Yes, that is one beautiful piece of work. Congratulations!

I hope this one gets built and tested many times here. It will be interesting to see the fueling variations that will undoubtedly be attempted.

Very nice compact design.

L Cottrill

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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by GRIM » Fri Feb 13, 2009 8:13 pm

Hi M
Congratulations , to you and Rosscoe , a beautiful piece of work , a GREAT name, and well worth the wait,

Thanks to both of you for your time and effort and for sharing this with the pulsejet community,

I intend to “attempt” one of these , it alas wont be stainless , and almost certainly wont be as pretty as the pictures , but I daresay will make some noise !!!

Thanks again, will keep you informed of progress

G

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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by Mike Everman » Sat Feb 14, 2009 6:53 am

Yes, very nice work, M and Rossco! I may just break the little motor rule... naw, but looks pretty enough. 48 downloads since unveiling... In the words of Darth Vader, "most impressive".
Mike
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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by Fricke » Sat Feb 14, 2009 3:34 pm

Very nice and good looking engine!
"woot"
A shrill, obnoxious noise/word used by immature people to express happiness or excitement.
Supposedly started in the gamer community, but is now used by any slack-jawed moron to express delight.

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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by Ghrey » Sun Feb 15, 2009 8:08 am

It does seem "Eloquent"


I will likely have questions.


I am making progress on clearing shop space...
In the process of moving, from the glorified phone booth we had to the house we have.

No real time to work on jets, more space, no time.

Life still complicated.

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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by Johansson » Sun Feb 15, 2009 8:42 pm

Great work guys! :D

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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by larry cottrill » Mon Feb 16, 2009 12:34 pm

I especially think the flow-shaping "inverted sombrero" front end is a highly innovative touch ;-)

L Cottrill

hinote
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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by hinote » Mon Feb 16, 2009 6:53 pm

Hello M.:

Can you provide us with your expectations regarding TSFC, operating frequency and acoustic temp?

Also, has a first article been built and tested yet?

Bill H.

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POST BUILD QUESTIONS HERE, PLEASE

Post by milisavljevic » Tue Feb 17, 2009 4:01 am

Greetings Everybody --

First of all, Rossco and I thank you for the compliments, many of which were received via email or PM. :D

I have also received a large number of build related questions by PM, and while these are all answered
by PM, I would encourage any one with build questions to ask them here, so that all benefit from what
we have to say! For this reason, as time permits I will copy / paste all relevant snippets to this thread.

Again...please post all build related questions to this thread. Thanks in advance! :D

Cheers!
M.
no safe haven for merchant scum


for ye merchants who do the prop'r t'ing only if
ye be haul'd-up on charges b'fore ye ship-mates
an' threat'nd wit' forfeiture of all ye precious loot
hear this - so-called stand-up guys YE BE NOT

avast!
Cap'n M.

milisavljevic
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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by milisavljevic » Tue Feb 17, 2009 4:16 am

Hello Metiz --
metiz wrote:Is there a particular reason why there is no straight tail pipe section?
A better question is: "Why would anyone ever build a tailpipe with a constant-diameter (ie., 'straight') section?" *

Think on that a bit, and I will get back to you. :wink:

Cheers,
M.

* Note: excluding u-bends, although Snecma demonstrated that even these need not be constant-diameter. :wink:
no safe haven for merchant scum


for ye merchants who do the prop'r t'ing only if
ye be haul'd-up on charges b'fore ye ship-mates
an' threat'nd wit' forfeiture of all ye precious loot
hear this - so-called stand-up guys YE BE NOT

avast!
Cap'n M.

milisavljevic
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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by milisavljevic » Tue Feb 17, 2009 4:38 am

Hello Larry --
larry cottrill wrote:I especially think the flow-shaping "inverted sombrero" front end is a highly innovative touch.
While I'm glad you like that bit, you really should take a closer look at the plans. The rendered images
make the combustor cover "dishing" appear much deeper than it is, so it's not there for "flow-shaping".

This "feature" first appeared on sc(h)-8.8g1 and sc(h)-8.9g1, Mike's and Fredrik's collaborative entries
in the forum challenge, respectively. Mike has yet to build his; Fredrik's duct is awaiting "test weather".

Not discounting any effects it may have wrt. combustor circulation, the real purposes are: (a) relocate
the spark plug away from the front of the duct to enforce my zero footprint "rule"; (b) strengthen the
cover against warping; and (c) not used in Thunderchine: tune the combustor volume via cover recess.

That being said, if someone really wants to pound in a "sombrero", have at it. Lower thrust me thinks! :wink:

Cheers,
M.
no safe haven for merchant scum


for ye merchants who do the prop'r t'ing only if
ye be haul'd-up on charges b'fore ye ship-mates
an' threat'nd wit' forfeiture of all ye precious loot
hear this - so-called stand-up guys YE BE NOT

avast!
Cap'n M.

milisavljevic
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Re: "Thunderchine" 55 lb thrust pulsejet plans

Post by milisavljevic » Tue Feb 17, 2009 5:14 am

Hello Bill --

Operating and performance specs for Thunderchine will be posted as soon as time permits;
I have been rather busy answering build related questions (see my post above). No secrets.

[snip]

Given the delays in getting plans posted, there was time to have a first article fully tested;
however, none exists at the moment. I'm confident in this design's predicted performance.

If it will help your calculations, built-to-spec units will lock in at 159 Hz and peak at 164 Hz. :wink:

Cheers,
M.
Last edited by milisavljevic on Wed Feb 18, 2009 3:01 am, edited 1 time in total.
no safe haven for merchant scum


for ye merchants who do the prop'r t'ing only if
ye be haul'd-up on charges b'fore ye ship-mates
an' threat'nd wit' forfeiture of all ye precious loot
hear this - so-called stand-up guys YE BE NOT

avast!
Cap'n M.

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