well /diy/ i got good news.... just dropped like 750 dollars on various propane fittings, hoses, pumps, regulators, ext for the fuel and oil systems of the home made jet engine im making. when i get back to my work garage mid august, i should be able to throw this togeather and give you guys some OC.
so, ask questions, i have done a shit ton of research on it, and i wish i could have had someone to q&a.
>>1011423
do you have some diagram of that system and how should it work
what will be fuel relative consumption
>>1011423
jet engine Axe and blades are made of a specific alloy called inconel, this alloy is very hard to fogs and is stupidly expensive too.
i hope you already know that, an engine out of regular steel will not last you more than few runs
>>1011431
i thought the blades were made of titanium, although the melting point of the two arent very far apart (~300ºc)
>>1011436
depend which blade. you can get away with making compression blades out of light materials, but the exhort blades have to be made out of inconel. otherwise they would melt
>>1011445
but titanium has a higher melting point than inconel (at least according to google), wouldnt that make it better suited for the exhaust ones (i thought even the intake/compression ones were titanium)?
>>1011452
not sure man, i'm not an alloy specialist.
i just know that they use inconel.
i found this http://www.mclarenlife.com/forums/mclaren-650s/39337-inconel-vs-ti.html
apparently inconel is more heat resistant than Titanium.
Titanium may not be as rigid and probably bend
https://www.youtube.com/watch?v=Gh34A0b8MrE
>>1011452
The blades are single crystal inconel "superalloys". They have incredible heat resistance and resist deformation incredibly well. Mainly due to how the grain structure follows the same order throughout so it doesn't have extra stress or deformation at the grain boundaries because there are none
>>1011429
Not on my phone, I'm walking to work currently, I can later. Also got a YouTube video of a disassembly of the flame tube I can post.
>>1011431
Yes, I'm aware. The turbine I'm using was real cheap... Like reeeeal cheap. But it seems to be halastoy for the turbine and aluminum on the compressor. Might melt a blade. Worst case I get a better turbine and call it a day.
>>1011492
>The blades are single crystal inconel "superalloys".
First off--what real actual jet engine companies use is the most-exotic, most-expensive and highest-performance materials they can get in the whole world.
You probably couldn't even find a source to buy small quantities of that stuff if you tried; the only way you can buy it at all is if it's already made into a jet engine part.
-------
So back to reality: what small jet engines and turbochargers use is a class of metals called 'high-nickel steels'. Inconel and Hastelloy are two examples.
McMaster-Carr does list a high-nickel steel on their website, that you can buy (pic related).
In addition to being not cheap (a bit cheaper than titanium) it is also difficult to machine. It's prolly gonna eat at least one (carbide) mill bit. And that mill bit is gonna cost you $40~$50 more. (-EDM may be cheaper here, I dunno. I would check into that first-)
Mail-order metals places normally charge at least 2-3X what a local supplier will, but the problem here tho is that high-nickel steel is a fairly exotic metal and isn't used for a lot of stuff.
I would call around to local metals places first to see if they can get it cheaper than that,,,, but don't be too surprised if all of them say they have no source for it.
If I was doing this, I would just make the first version out of regular (carbon) steel to get it working properly. Assuming the engine's diameter isn't more than a few inches and you aren't overheating the turbine, it should do okay up to 10K or 20K RPMs at least.
AFTER you know everything works, then you could go back and try to cut some rotors out of a nickel-steel, in order to allow the thing to run at faster RPMs.
>>1011492
This sounds really cool. The question is, can I make it myself?
>>1011548
Yeah, the turbine I'm using is from a turbocharger. It appears to be hastealloy
>>1011554
Make as in the alloy? Or the turbine? The first is very very unlikely. Forge you would need would have to reach and sustain very high temperatures, and the process is going to be proprietary and near impossible to find (if I had to guess).
As for the turbine, yeah. Materials would be pricy. But if you had a 4 axis mill with a big enough motor, sure. That mill is going to cost tons and tons, so unless you have access to one, then no to that as well.
>>1011554
Sure you can, people do it all the time. Just plug in your HTB furnace and start measuring out amounts of iron nickel and chromium. Oh, you'll also want to start warming up your X-Ray diffraction machine. About 20kV 40mA should be fine to start.
>>1011548
you can buy it. But it's easier if you're doing research or working for an aerospace company
sup guys, im back.... alright, let me try and explain how this works...
i do a lot of my idea sketching pen and paper, but i have been CADing some suff so i can do stress analysis. so, i dont have the inner flame tube made (no real stress on that, that was done on drafting paper), but im working on cading that, or i might just post the youtube vid where i show the disasembly.
heres the combustion chamber. the small tube coming off of it is where preasurized air from the compresser flows in. it mixes inside of this, though the flame tube. once mixed, it is ignited by a smark plug, and slows down along the flame tube. at the other end, it exits, and enters the turbine, which is what keeps the compressor spinning and the cycle continues. the extra energy is the thrust you get.
>>1011804
So you're doing a bog standard turbocharger radial engine with one flame can. This shit's well documented and can be done crudely by teenagers and still work.
Don't get me wrong, I wanna build one too.
>>1011804
on the left you can see the two other plates, the small one with 2 holesif the fuel inlet and spark plug hole. the other plate with the largr hole is where the exhaust gasses come from.
>>1011807
currently yes, in the future its going to be an on axial engine with 8 flame tubes. i only have a 3 axis bridgeport right now, in about a year and a half ill have a 4 axis so i can make my own compresser and turbine
>>1011554
Sure, if you want to spend 10 years getting a metallurgical degree and hundreds of thousands of dollars on equipment.
But seriously, no. Go for carbon steel or stainless.
>>1011562
>Yeah, the turbine I'm using is from a turbocharger. It appears to be hastealloy
Well then the rest of it is fairly easy, since you can just make the whole casing out of regular carbon steel.
The only parts that require high-strength alloys is the parts that spin.
>>1011554
>can I make it myself?
not unless you have few millions to spend on it
