Questions about making a Junkers 004 jet engine

[stukahunter]

Hello

I am currently at a highschool for engineering and machines and I love planes, easpecially world war 2 planes. So much so, I would like to make one for my graduation product. I found this forum and ill give it a shot with questions etc. But first let me explain what I would like to build:

A Junkers 004 axial flow jet engine, which is in smaller scale than the original (about 1/2, ill see), which would be built by materials Germans used in their factories in reality (no fancy aluminium etc, just plain steel, to demonstrate that it can be done, but at a cost of reliability) and run on the same stuff as IRL, gasoline. Fuel would be pumped straight into the chamber through hoses. The APU unit at the front would be ommited and instead something like air hose would be used to start it. The fuel would be ignited by spark plugs. The fuel and spark plugs would be monitored and controled by a throttle lever.

So basically a downscaled 004 with some practical adjustments.

But I have some questions:

-What do you think about my adjustments and would they work? If not, suggestions are welcome.

-What equipment do i need to produce such engine?

-In what time is it possible to make one?

-Would it be dangerous to use?

-What would be a lifetime of such engine?

-Is it possible to buy certain complex components (like throttle system etc.)?

Every answer and suggestion is highly appreciated.

[BFTO]

That is one huge and complex project, maybe 10-20years if you have a fully equipped workshop and a brain the size of Anselm Franz.

Not to be a partypooper, you should look at a single centrifugal compressor design. Junker 004 is a single centrifugal compressor AND eight axial compressors. The 004 lifespan was max 25h because of inadequate heat resistant materials.

[jetjeff]

Hello,

Making a 1/2 scale Jumo engine would be a HUGE undertaking. Part of the problem is the efficiency of the rotor and engine as a whole decreases as the scale is reduced (this applies to axial and radial gas turbines). I'm a huge fan of WW II aviation too. Two books you may want to consider getting is "Turbojet history and development 1930-1960 volume 2" by Antony L. Kay and "The history of German aviation The First Jet Aircraft" by Wolfgang Wagner.

At a high school level I would recommend either a turbocharger based turbine with external combustion chamber or a Schreckling based jet engine. To be honest I've only seen a handful of small axial flow engines that ran on YouTube.

A Schreckling engine can be built with a small table top lathe, a drill press and a MIG welder. An axial flow engine would require a full blown machine shop to have any chance of running at all.

All turbines have a certain amount of danger. Schreckling states in his book "every imaginable type of fragmentation has occurred, including the rotor ripping itself out of the housing",,,be forwarned.

Life of the engine is dependent on the bearings, Schreckling and Kamps recommended replacing the bearing after 25 flights.


Velka Bytes is a company in the Czech republic that does have an apprenticeship program, not sure if it's open to folks outside the Czech republic, but it might be right up your alley.

Regards

Jeff Pittel

[stukahunter]

Thank you for the answers so far.

I looked at the Schreckling engine and it seems like a nice thing to make. What is that coil inside of it though, and how long would it take to make one aproximately?

[jetjeff]

The coil is the vaporizer,,,liquid fuel is turned into a gas as it progresses through the coil. It is not used anymore,,,there have been updates to the original combustion chamber. Look at my Old + New thread and Heineken part II,,,these are pretty much Schreckling engines.

My first Shreckling engine took 9 months,,,Heineken part II should take considerably less.

Regards

Jeff

[racket]

Maybe checkout the GTBA www.gtba.co.uk/

[jetjeff]

Hi Ju88 hunter,

I worked for Volkswagon of America for 13 years right after high school. German passion for engineering was evident when I worked for them. It's not surprising they were decades ahead of the reset of the world during WWII.

Regards

Jeff

[jetjeff]

Hi Stukahunter,

Was thinking about your first idea, then a second option hit me. I have plans for a pulse jet, if you're interested I can mail you a copy of them. Pulse jets are pretty simple to construct and your high school tech school may have sheet metal bending equipment. Let me know.

Regards

Jeff