serverlan wrote:Hey all,
I'm starting to investigate H2O2 for thrust for a rotor-tip jet
for my gyrocopter. (haven't learnt to fly yet - soon - so I thought if I start investigating now, then it all might come together in a couple years...)
Axt, you are in Australia too? I'm near Canberra.
Where do you get concentrated peroxide from? What does it cost?
I was planning to use catalytic breakdown rather than use it as an oxidant with a fuel, as there are no ignition problems. Easy to throttle, etc.
I was thinking of platinum as catalyst. Now, this might sound silly, but you only need a little. Is surface area that counts, not mass. So
option 1) - old razor blates - platinum coated edges.
option 2) - platinum wire
option 3) - build my own electroplating tub
and now you tell me plain old brass will do it?
The plan was for a stainless steel tank mounted atop the rotors,
and a throttle system based on pushing upwards with a cable or rod at the centre of rotation, just letting the tank spin around the rod.
The H2O2 would then flow down a tube inside the rotors to catalist and jet nozzle at the tips of the rotors.
The result should be an excellent prerotator, with a bit of VTOL capability.
Capable of operating as gyro or limited helocopter, or a mixture of both.
I noticed that there is info on ramjets here that gove indicative thrusts for helos at bout 30 lb.
Should be easy with H2O2.
There is a site with an outrageous go-kart that produces 1500 h.p. through a turbine at 18,000 rpm and 1 litre of H2O2 per second.
30 lb thrust should be a doddle.
I will also need to build a still to purify the H2O2.
Ok, now stop laughing and give me some meaningful feedback! ;)
Don
It's been gone over before, but please be carefull of any distillation of hydrogen peroxide.
1) You can't distill it in the traditional sense. You'll end up with distilled water.
2) You can't freeze it out. (see rule one)
3) You can only vaccuum distill it, but you need boron silicate glass or you end up with impurities. And the impurities might cause a spontaneous explosion. (might should read usually)
4) The ISP between 50% and 90% is so negligible it's not worth the extra effort. Plain old food grade Hydrogen Peroxide will probably give you what you want. Look around your local larger cities. Someones bound to have it.
5) Wear eye protection. You can live with the decomposition you'll get if it splashes on your skin, but if you get it in your eyes, kiss your eyesight goodbye forever. There's no way to stop what'll happen.
6) There's very few if any decent plans available to build Hydrogen Peroxide rockets. Simply because Hydrogen Peroxide is too crappy a oxidizer to use safely. It's hard to handle, has a low specific impulse, and weighs a ton. Hey, to each his own though. Find premade plans though. Again, if you screw up with this stuff, it'll kill you dead before you have a chance to correct your mistake (contaminants are it's worst enemy).
I built a SS-67B1 back in '99
Link from the old thread
http://www.pulse-jets.com/oldforum/se.p ... m=pulsejet
Personally, I'd never do it again. Cost plus the danger just wasn't worth it.
Oh, before I go. You'll need a budget in the $2500~$6000 range to do this (even with the plans) to get this safely off the ground. It's not a cheap hobby.
Couple of sites for you;
http://www.h2o2.com/
http://webhome.idirect.com/~earlcp/FAQs/FAQ.html