Author Topic: Fluorine  (Read 134542 times)

Offline jdbenner

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Re: Fluorine
« Reply #75 on: March 24, 2011, 05:56:30 PM »
I know that this has nothing to do with Florine,  But I read about a proposal to use liquid Oxygen as propellant in a Nuclear Thermal or Solar Thermal Rocket.  The Only reason that this was proposed, is that Oxygen could in principle be extracted from Lunar Regolith or Rocks.

Another thought (This one mine) is the idea of using multiple propellants in a Nuclear Thermal Rocket.  First a dense or plentiful propellant is used and then a switch is made to Hydrogen.  This is the same Idea behind proposed Tri Propellant Chemical Rockets.
Joshua D. Benner Associate in Arts and Sciences in General Science

Offline ijuin

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Re: Fluorine
« Reply #76 on: March 24, 2011, 10:27:54 PM »
The thing is that there probably isn't any cheaper/more plentiful propellant that is liquid in a lightly insulated tank than water, unless you are on Titan where you'd want light hydrocarbons instead. Pure oxygen is not only about 80% heavier than water by molecular weight, but would much more easily corrode the innards of your propulsion system--I wouldn't use it unless there wasn't enough hydrogen available to use water instead.

A question for Bob or anybody who has the data set up for this: how does H2O perform as an NTR propellant as compared to the others examined earlier in this thread?

Offline Bob B.

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Re: Fluorine
« Reply #77 on: March 25, 2011, 07:39:49 AM »
A question for Bob or anybody who has the data set up for this: how does H2O perform as an NTR propellant as compared to the others examined earlier in this thread?

I considered water earlier in the thread, but dropped it from later calculations because its performance wasn't very good.  Look at Reply #50 on Page 4.

Offline ijuin

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Re: Fluorine
« Reply #78 on: March 26, 2011, 02:27:16 AM »
Looks like we're best off sticking with methane in that case unless carbon is unavailable, though I still wouldn't want to try using pure O2 unless hydrogen isn't available.

Offline jdbenner

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Re: Fluorine
« Reply #79 on: March 26, 2011, 03:58:34 PM »
I still wouldn't want to try using pure O2 unless hydrogen isn't available.

Hydrogen is vary rare on the moon. unless we can tap the ice trapped in poler craters.

 But if water is readily available it would work better. The problem is, water could be converted to Hydrogen oxygen chemical propellant with better performance. the only advantage in using water as a propellant in a solid core nuclear thermal rocket is reduced material processing requirements, VS chemical propellants.
« Last Edit: March 26, 2011, 04:01:19 PM by jdbenner »
Joshua D. Benner Associate in Arts and Sciences in General Science