Oxidizer (question)

Gerdih

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Do you know about a liquid oxidizer appropriate for amateur rocket engines?
Cheap, non toxic or slightly toxic and liquid in ambient temperature.
I am looking for H2O2 but I see that 30% its expensive

Thanks
 

Urwumpe

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laughing gas (N2O) could also be used, and it is pretty easily acquired.

[ame="http://en.wikipedia.org/wiki/Nitrous_oxide"]Nitrous oxide - Wikipedia, the free encyclopedia[/ame]
 

kwan3217

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Just make sure you know what you are doing. The guys at Scaled Composites had an engine explode on them, and they were using nitrous oxide as an oxidizer (with solid fuel).
 

ar81

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A good rocket is the one that uses fuel that does not make the maker to be part of the chain reaction and does not put the maker within the range of gas expansion...
 

Urwumpe

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That's only a matter of pressure & temperature :)

exactly - At room temperature, liquid nitrous oxide is self-pressurizing at 2.5 MPa.
 

Gerdih

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Yes but I dont want to buy a tank every time that I will test the engine
I need liquids in ambient temperature and ambient pressure.

---------- Post added at 02:28 PM ---------- Previous post was at 02:24 PM ----------

I think that H2O2 90% or 80% is prefect
Somebody know where I can get it cheap?
 

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Yes but I dont want to buy a tank every time that I will test the engine
I need liquids in ambient temperature and ambient pressure.

Have you already realized that you are going to develop a rocket engine?

If you don't understand what powers you want to harness, let it be and buy professional solid rocket motors in a shop, instead of building them yourself and risking the health of you and the people around you.

BTW: H2O2 is more likely to explosively decompose on contact with the wrong material. The USSR lost a R-7 rocket in a massive explosion because somebody just used the wrong welding metal for fixing a leak in a H2O2 tank.

If you are not willed to work with such dangerous technology in a responsible and professional way, don't do it. If you are lucky, you will only loose your hand otherwise. In the worst case, you will not only kill yourself, but also friends and family around you.
 
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Gerdih

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However, If Nitrous Oxide is easy to get I can use it but the program that I use to calculate some thermodynamic data dont have it(RPA V.1.0). Do you know about any program to calculate combustion chambers data?

---------- Post added at 02:37 PM ---------- Previous post was at 02:34 PM ----------

Have you already realized that you are going to develop a rocket engine?

If you don't understand what powers you want to harness, let it be and buy professional solid rocket motors in a shop, instead of building them yourself and risking the health of you and the people around you.

BTW: H2O2 is more likely to explosively decompose on contact with the wrong material. The USSR lost a R-7 rocket in a massive explosion because somebody just used the wrong welding metal for fixing a leak in a H2O2 tank.

If you are not willed to work with such dangerous technology in a responsible and professional way, don't do it. If you are lucky, you will only loose your hand otherwise. In the worst case, you will not only kill yourself, but also friends and family around you.


You are right, T_T Well, I can use pressurized air as oxidizer no? It will be more safe?
Air/Gasoline
 
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Loru

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You are right, T_T Well, I can use pressurized air as oxidizer no? It will be more safe?
Air/Gasoline

I will be surely safer than H2O2 or nitrous oxide but remember that only ~20% of air serves as oxidizer. That is the reason compressors are crucial part of jet engines.

If you're building test engine only to perform groundtests you may consider using presurized O2 tanks (used eg. for quartz glass welding or in rescue & medical application).

As fuel you may use any flamable liquid (kerosene, gasoline, diesel fuel). Main advantage is that O2 suply can be easily moderated by electromagnetic valve, while liquid fuel can be controlled by speed of the pump.

Anyway write some more about scale of the project - Will it be a small test platform only, or you're planning flyable engine.
 

Gerdih

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This Engine only for test.
I think that will be more safe air than O2 and I can get air easy with a compressor.

Maybe I use O2 in future engines but I dont think so. Its easy to get and cheap?
 

Loru

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Well. In Poland compressed oxygene in tanks is quite easy to obtain (there are points where you can go and fill your tank with O2, CO2, N2, C2H2, or propane-butane mix) They're sold for welding purposes.

I don't know how expensive are they but surely you can search and call similar point near your location. They'll tell you all things you should know about storing, transporting and required permits or certificates (if they are nescesary).

On safety - simply you don't store your O2 tanks near the engine. Instead O2 should be supplied by some sort gas-pipe installation from a distance. You can avoid direct contact of large quantities of fuel & oxidizer this way. You don't have to put all things in one place.
 
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