In specific applications, jet engines are often the most efficient internal combustion engines available. Not just for airplanes, but for anything that needs to run on a wide variety of fuels, operate at a consistent high RPM, or run for an extended amount of time. Of course, most people don’t have an extra $4,000 lying around to buy a small hobby engine, but now there’s a 3D-printed axial compressor available from [noob_sauce].
As an aero propulsion engineer, [noob_sauce] is anything but a novice in the world of jet engines. This design is on its fourth iteration with a working model set to be tested by the end of the month. Additionally, [noob_sauce] created his own software that was necessary for the design of such a small, efficient jet engine which has all been made available on Git. So far the only part that has been completed has been the compressor stage of the engine, but it’s still a very impressive build that we don’t see too often due to the complexity and cost of axial compressor jet engines.
Of course, there are some less-complex jet engines that are available to anyone with access to a hardware store and a welder which don’t require hardly any precision at all. While they’re fun and noisy and relatively easy to build, though, they don’t have near the efficiency of a jet engine like this one. The build is impressive on its own, and also great that [noob_sauce] plans to release all the plans so that anyone can build one of these as well.
“In specific applications, jet engines are often the most efficient internal combustion engines available. Not just for airplanes, but for anything that needs to run on a wide variety of fuels, operate at a consistent high RPM, or run for an extended amount of time.”
Jet engine hooked to a home generator, hmmm.
Turbine Generator in a Suitcase.
“Jet engine hooked to a home generator, hmmm.”
Like Pinkerton: “We never sleep!”
Look up “capstone microturbine”
I need to find a used one as a range extender for my electric truck.
25 – 30 kW would be enough to maintain highway speed. ;)
An an option, some of the APUs for helicopters are basically hand-portable. Might also be easier to find used.
APUs are used in many aircraft, as well as tanks, and other military equipment. Dr. Marius Paul converted many small turbos into APUs for special applications. (Engine Corp of America.) RIP Dr Paul.
But they’re not exactly fuel efficient or designed for prolonged use, would need a fair bit of modifications…
Sure, just add some magnets to the turbine shaft and wind some stator coils around it. Extra efficiency points if you add in a steam engine powered by exhaust heat. These things are pretty common if you need a few megawatts, but you usually don’t see them in home sized applications.
You might be better going homopolar Faraday disk style. The high rpm would be a huge advantage. Loads of amps.
Also check out http://amazingdiyprojects.com/3D_jet_engine.html, parts are 3d printed or casted with 3d-printed molds.
Looking forward to see how this new [noob_sauce] compressor performs, I was told axial compressors would be really difficult to get working at this kind of scale. And indeed even the commercial RC jet engines use centrifugal compressors. I think I’ve seen one engine with an axial compressor on youtube but that used many stages and was a cnc machining masterpiece, a really really complex build.
It is indeed hard to get these working properly at this scale. That’s why my stages are so oddly shaped – the calculations tried to compensate for the inlet axial speed using the rotational speed and large area blades which returns to normal once deep in the compressor.
I’ve always wondered about a hybrid approach as most of the early engines did. Why not do a centrifugal final compressor stage? This would keep impeller size small and probably easily get double the compression of the entire rest of compressor/gas generator section. The turbine and combustor will remain incredibly difficult. kudos and I’ll be following this with great zeal btw.
I’ve actually toyed with the hybrid version, even going as far as to design the centrifugal compressor. The math behind designing one of those is significantly harder than axial. Which is strange. But if this underperforms, I’ll definitely pick the centrifugal part back up to see if I can compensate.
I’ve actually toyed with the hybrid version, even going as far as to design the centrifugal compressor. The math behind designing one of those is significantly harder than axial. Which is strange. But if this underperforms, I’ll definitely pick the centrifugal part back up to see if I can compensate.
So can these be printed in PLA and then lost-wax baked out in an oven to cast AL?
It might be possible to do a crappy steel turbine to drive the cast compressor and just run it off of LP.
I bet an exhaust shop could do the hourglass shape tube for the housing.
Every few months I scope auctions for a nice Garrett APU and dream of an experimental jet conversion of a glider.
Printing in PLA then casting in Al is the plan. I’m doing a prototype build right now for sanity’s sake, then after it passes I’ll do the PLA build and pray.
Just to point out, this is not a jet engine. They are only designing the compression part.
“I built this to be run with an electric motor. I wasn’t planning on building a combustion or turbine stage.”
I think Jaguar cars built a hybrid jet turbine/electric car along the lines that a turbine is most efficient on a constant throttle so it runs a generator at a constant speed and electric motors drive the vehicle with the added benefit of regenerative braking.
My grandson 3d printed a rocket engine last year.. Kinda cool.
Here is the launch: https://www.sedsucsd.org/launch/
SEDSUCSD had a display at a rocketry exposition in the Nakaoka Center in Gardena, CA. I took my five year old an the members of SEDS were great. I felt like 3d printing wasn’t necessary to achieve the results, but for proof of concept it was a quite valuable. They are a great group of student engineers. You should be very proud that your grandson is one of them.
40K RPM with a 3D printed PLA centrifugal impeller. https://www.youtube.com/watch?v=logxPDmEUiI