Turbojet engine mk.1

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does this look promising?

hell yeah!!!!
4
44%
mmmh......
5
56%
 
Total votes: 9
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DYI
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Sat Apr 12, 2008 1:23 pm

I'm rather confused as to how you're going to get a high enough flow rate out of a propane tank to power this thing to the point that it can push a bicycle along.
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CpTn_lAw
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Sat Apr 12, 2008 2:36 pm

You would be surprised of the full potential of a propane tank, and i won't be using a pressure regulaor. Plus i'm gonna use the oil line that i'll wrap around the propane bottle to use the heat to maximize the propane pressure, and cool down the oil. max RPM = 210,000 , max working temp would be around 700°C. tomorow i'll weld the waste gate, and improve the turbocharger as I need to see clearly what i must work on. No play at all on the shaft, but the turbine doesn't spin very freely. i need to figure out why.
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miskaman
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Sat Apr 12, 2008 2:50 pm

CpTn_lAw wrote:You would be surprised of the full potential of a propane tank, and i won't be using a pressure regulaor. Plus i'm gonna use the oil line that i'll wrap around the propane bottle to use the heat to maximize the propane pressure, and cool down the oil. max RPM = 210,000 , max working temp would be around 700°C. tomorow i'll weld the waste gate, and improve the turbocharger as I need to see clearly what i must work on. No play at all on the shaft, but the turbine doesn't spin very freely. i need to figure out why.
Is that even possible? Wouldn't something fail before it got going that fast?
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DYI
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Sat Apr 12, 2008 4:25 pm

That's some insanely fast spin you've got there. Your average rifle bullet spins at around 100 000 rpm, and that's sometimes lead, which is rather weak compared to steel or aluminum, so this thing should be able to hold together if it's built sturdily enough.
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POLAND_SPUD
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Sat Apr 12, 2008 5:26 pm

15 kg thrust is quite a lot... I don't think it is safe to try that with a bike but hey who cares :-D
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DYI
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Sat Apr 12, 2008 6:01 pm

It depends on the size of whatever's spinning, but even if the rotor was 2" around, the outer edge would be moving at speeds approaching Mach 2. Better make sure that there's nowhere for shrapnel to get out if the rotor breaks, because it could slice you up pretty good at that kind of speed.
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CpTn_lAw
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Sat Apr 12, 2008 8:49 pm

Lol don't worry, i know it can sound crazy. In fact, the outer edge of the compressor inlet is 2.5 " diameter , at 210,000 rpm, or 3500 rps, that makes 2300 ft/s so you're absolutely right.
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miskaman
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Sat Apr 12, 2008 9:12 pm

Wouldn't you have to have a PERFECTLY absolutley balanced rotor for it NOT to wobble going that fast?

Because if you got even the smallest wobble going at that speed, I don't think there would be much left of the object it would hit.
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CpTn_lAw
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Sun Apr 13, 2008 4:49 am

Indeed, you have to have a maximum of .001 mm incertainty concerning the spacing of the shaft in the bearings. Fortunately enough for me, i have this margin. I'll post a picture of the weld as soon as it's done!
"J'mets mes pieds où j'veux, et c'est souvent dans la gueule."
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rp181
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Sun Apr 13, 2008 11:51 am

have you looked at pulse jet engines? They seem a better way to give thrust then your way, constant ignition isnt needed, the main problem is it gets really hot. A well built one made of copper would start to melt solder within seconds. No air imput is needed, just propane, it draws its own air in. welded steel is a must.
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CpTn_lAw
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Sun Apr 13, 2008 2:48 pm

A turbojet engine doesn't require constant ignition. Once it at idle speed, it sustains itself. And, as I stated before, I don't want something easy to build.
"J'mets mes pieds où j'veux, et c'est souvent dans la gueule."
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Jeeperforlife
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Mon Apr 14, 2008 9:33 am

Looks good.
I have been wanting to build one of these for some time to run on kerosene, I have 150 gallons I need to dispose of.

Great, just what i need another project.
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RDX,
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Thu Apr 17, 2008 1:09 pm

you have the same project as I :D , my turbo is KKK-K26 :wink:
I haven't done much but I have the turbo and some plans for piping 8)
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