/diy/ - Do It Yourself

>>1181023
>>1181041
>>1181667
>All these naysayers
You'd be amazed what you can get away with and still make a working turbojet engine.

https://www.gtba.co.uk/engine_designs/
https://www.scribd.com/doc/3746230/Gasturbine-Engines-for-Model-Aircraft
>Dremeled-up stainless sheet for a turbine wheel?
Sure.
>Bicycle-hub spool?
Why not?
>Camp-stove combustor?
Perfect.
>Propane cylinder for housing?
Great!
>Wooden compressor?
No fucking problem.

>>1181914
It's been done before with fuel-oil, I don't see how alcohol would be any less viable.
Flash boilers can be pretty lightweight.
All that said, whether or not a LARPing /pol/tard like OP can pull it off is an entirely different question.

>>1166711
Here's the classic homebuilt model turbine design:
https://www.scribd.com/doc/3746230/Gasturbine-Engines-for-Model-Aircraft
Obviously if you have access to CNC, you can probably make something more elegant. But it still goes to show what you can get away with and still have a functional jet (wooden compressor wheel? No problem).

>I mean where does the combustion exactly happen why are there two tubes overlapong the other
I think the combustor in your picture is a basic form of annular combustor. Combustion is confined to a thin ring between the inner and outer tubes, and "cool" compressed air flows through both walls into this annulus to keep the flame confined and away from the walls.
>The placment of holes diameter of differrent holes and their number, why? Please explain, and give me a good source for this.
Dunno, most combustors I've seen have more holes and they're mostly the same size. Then again, Schreckling's burner has very few holes on the inner surface, and none on the outer surface. I'm sure you can get away with a lot more running low pressure ratios, especially if you don't particularly care how long the engine lasts.

>>1002120
>I understand that from a efficiency standpoint, a plain ol' diesel generator will be much better than a turboshaft for electricity generation.
A /diy/ turboshaft, yeah probably. But more generally-speaking, nah. Aircraft turboshafts/turboprops are fairly inefficient since they prioritize power-to-weight and reliability over raw efficiency, but marine turboshafts and those gas turbines used in power stations can beat out pretty much all "plain ol' diesels," with only those gargantuan 2-stroke marine turbodiesels surpassing them.

But anyways.
>What kind of tools would I need to make the blades and such?
How "right" do you want to do it? If you don't really give a fuck about performance or longevity, you can actually get away with pretty lean methods using very basic tools and materials. For example, Kurt Shreckling designed and built an outrageously-/diy/able, working centrifugal turbine engine (pic related), featuring a turbine blisk that's cut, bent and dremel-ground from a scrap of sheet-steel, and a compressor made from fucking plywood:
https://www.scribd.com/doc/3746230/Gasturbine-Engines-for-Model-Aircraft

If you want to follow the "homebuilt turbine engine" cliche, you could repurpose a turbocharger fairly easily as well, and probably achieve better performance than the Schreckling design (just as long as weight isn't a factor, that is) by running higher pressures and temps

Both of these options would require you to somehow integrate your own PTO to the shaft, or better yet you could build a separate multi-stage power-recovery turbine driven by the core exhaust as most turboshafts are.

If you're looking for more conventional manufacturing methods, see here:
https://www.youtube.com/watch?v=hOv2pGEruGk
Of course, modern engines often use blisks instead. Perhaps you could 3D-print a blisk pattern and cast that. Also you may not have the resources to cast nickel superalloys at 3000*, so watch your ITT/fuel flow if you use steel or whatever.

>All these naysayers
OP, go hunt down the book "Gas Turbine Engines for Model Aircraft" by Kurt Schreckling. It explains how to build your own simple single-spool turbine engine (pic related) with a single-stage axial turbine wheel, cut+bent+ground out of a slab of ordinary sheet steel with basic tools, along with a single-stage, centrifugal compressor of wooden construction (I shit you not). It's crude as fuck but it does work.

Alternatively, pulsejets are even easier to make but a lot more troublesome to use due to their deafening loudness, finnicky ignition and a plethora of other issues. But if Colin Furze can do it, it can't be that hard.
https://www.youtube.com/watch?v=bCsg5pQimWI