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New Aluminum-Ice Rocket Propellant Tested
eldavojohn writes "With the problem of moving conventional rocket fuel to the Moon and Mars on their minds, researchers from Purdue and Penn State successfully tested and demonstrated the use of aluminum-ice (ALICE) as fuel. In a paper from last August they outlined how it would work (PDF), and now they know it does. Space.com also has more information on the paper and how nano-scale aluminum functions as a fuel."
I don't think you should be finding much aluminium in your piss.
Fly me to the moon. Let me play among the stars. Let me see what spring is like on Jupiter and Mars.
We spend so much time arguing with each other here on Slashdot, but when it comes down to it, we're all in this together. We are going to need to secure a future for future generations, so putting an effort into developing non-volatile fuels which can be formulated anywhere is one huge step towards getting off this rock.
Aluminum is plentiful anywhere we intend to go. This could really be the breakthrough that we've been looking for.
In other words, please be true. In other words, I love you.
One of these days, ALICE. Wham! Pow! Straight to the Moon!
I thought that said "Aluminium Rice Rocket", and I wondered why it was posted to /.
MIT Technology Review is a little late here. This was covered by numerous sources back in October. Surprisingly, I can't find it in the /. archives; so, it may not be a dupe.
> The oxygen and hydrogen in water molecules enhance the combustion of the
> aluminum.
"Enhance"? Um, the water _is_ the oxidizer.
Warning: this article may contain humor, sarcasm, parody, and perhaps even irony. Read at your own risk.
... propulsion?
Finally had enough. Come see us over at https://soylentnews.org/
For a neat visual presentation of the physics they're relying on, Mythbusters did an experiment on the explosive power of thermite powder and water vapor http://www.youtube.com/watch?v=BnHR4cMXiyM.
Isn't ice just the frozen liquid. Therefore, don't they just have to keep the aluminum from melting? Should be pretty easy, with the melting point around 1200F. I think you can buy pretty good frozen aluminum (renolds wrap?).
Who would win this election: Andrew Weiner vs Andrew Weiner's weiner.
Everybody know aluminum doesn't burn. Neither does water. Sheesh. ;-)
that highlight the safety instructions I've had at Aluminium plants. You never, ever, ever drop anything like used aluminium cans into the feed that is headed for melt shop as any bit of liquid still in the can will cause a rather powerful explosion
I am Slashdot. Are you Slashdot as well?
A better article on the engine here.
However I don't get how TFA considers this fuel as "environmentally friendly". Firstly one of the byproducts is aluminum hydroxide which, apart from helping us with our stomach ulcers, may be linked to brain disease - but I don't really care about that - the amount generated from a few rocket launches won't kill us all. But I argue that aluminum is not a naturally occurring substance - it has to be manufactured, and aluminum manufacture is the most energy intensive process around. So don't come to me with "environmentally friendly rocket fuel" when god knows how many tonnes of CO2 were dumped in the atmosphere to make the energy to refine that bauxite.
Still, if it works, it's better than "other" fuels that have extreme storage or environmental implications. Good for them.
Seven puppies were harmed during the making of this post.
Bang! Zoom! To the moon.
You see? You see? Your stupid minds! Stupid! Stupid!
It looks like the exhaust products should include a fair amount of hydrogen gas. If so, you could add a liquid oxygen tank, inject LOX upstream of the nozzle and burn the hydrogen that's freed up to produce even more thrust, and more importantly, a higher specific impulse. You might even be able to use it to create bimodal rockets that use the ALICE fuel for high thrust early in a launch and switch to pure H2/O2 later for the higher efficiency.
Wish those pesky scientists had thought of this earlier, we could have retired the B52s and had mach 3 bombers decades ago.
They whose government reduces their essential liberties for temporary security, receive neither liberty nor security.
Nano-scale aluminum can have quite useful and interesting applications. See for example here.
... in the form of aluminum oxides. It is most certainly not plentiful in the form of metallic aluminum, and the oxidized form is, well, already oxidized, and won't be oxidizing again in your propellant unless you reduce it first. Which takes an enormous amount of energy. Which means we're pretty much back to where we started. Not that ALICE is a useless technology, but you'll either need to haul your aluminum with you or make it on site - both of which would have significant problems.
http://www.wickmanspacecraft.com/wspcnews.html
John Wickman has been working on aluminum/oxidizer (LOX, not ice) motors since the 80s. His are intended to run on lunar soil.
Also in the can, a jet engine that runs on Martian atmosphere. Development from Oberth's original ammonium nitrate motors as an alternative to ammonium perchlorate.
Now working on NASA's SHARP re-entry vehicle. He's also one of the few pros that teach his craft at the amateur level and consult out to rocketers who want to carry out major projects.
"Rocket scientist" used to be a compliment. That fell away as they numbered into the tens of thousands and each did a tiny piece of engineering. This guy earns that title all over again.
"I may be synthetic, but I'm not stupid." -- Bishop 341-B
The whole premise of Ralph Kramden was, "You know that crabby bus driver, I wonder what he is like to his wife and friends?"
Ralph on one hand was supposed to be an object of the viewer's sympathy -- a working class guy barely making ends meet, living in a tiny apartment with his wife, barely any furniture or any other possessions to their name. On the other hand, Ralph was a blowhard, a guy with a chip on his shoulder, a fellow in humble circumstances who thought he was Center of the Universe, and yes, a guy who fought with his wife at times, even threatening domestic battery. That a guy like that even talked liked that was regarded as a "fact of life" back in the day, but it was part of the character portrait that Ralph could be the butt of our jokes, someone who perhaps deserved the laughs and ridicule that came his way.
On the other hand, a seemingly self-effacing mega-celebrity golf pro, suspected for cheating on his wife, leaves the house at 2 AM with his wife in hot pursuit breaking out windows on his truck leading him to crash into a hydrant and then a tree, found unconscious on the grass after being beaten about the head with a golf club, who refuses three times to meet with the cops and give a statement and "lawyers up" to keep his wife out of jail on zero-tolerance domestic battery laws put on the books to protect women from abusive husbands, now that is not funny either. And one does not laugh.
This technology only makes sense in a cold environment; Like the moon or the asteroid belt. Now; time to find Bauxite on the moon or asteroids. (ION drives are sounding better at this point, yes?)
... I'll have a Pan Galactic Gargle Blaster with a side of Plutonium Nyborg
Is it transparent?
Let me see what spring is like on Jupiter and Mars.
It's overrated and the lodgings really suck.
This is pretty close to that, exploding a suspension of a flammable dust in air.
I think you reach is far exceeding your grasp.
Perhaps you mean interplanetary space?
There is no right to feel safe thru security vaudeville at the expense of everyone's freedom, privacy and tax money.
How's a telekinetic, zombie-ass kicking clone going to help you get into orbit?
I swear to God...I swear to God! That is NOT how you treat your human!
Assuming a 2 to 3 Al to H2O molar ratio, it looks like the exhaust velocity is about 900 m/s so the Isp is about 90s.
: 1.458 g/cm^3
: 3166.569 : -7944.256 : -8685.762 : -33443.801 : 8.053 : 35.507 : 3.30500 : 3.00720 : 1.09903 : 1.09264
If that's right, that sucks compared to normal mixtures.
Of course, if you're lifting off the moon or asteroids, it may be ok. Mars? Probably not.
Computing case 1
Fixed enthalpy-pressure equilibrium - adiabatic flame temperature
Propellant composition
Code Name mol Mass (g) Composition
34 ALUMINUM (PURE CRYSTALINE) 2.0000 53.9631 1AL
976 WATER 3.0000 54.0458 2H 1O
Density
3 different elements
AL H O
Total mass: 108.008918 g
Enthalpy : -7944.26 kJ/kg
24 possible gazeous species
8 possible condensed species
CHAMBER
Pressure (atm) : 340.230
Temperature (K)
H (kJ/kg)
U (kJ/kg)
G (kJ/kg)
S (kJ/(kg)(K)
M (g/mol)
(dLnV/dLnP)t : -1.00584
(dLnV/dLnT)p : 1.13099
Cp (kJ/(kg)(K))
Cv (kJ/(kg)(K))
Cp/Cv
Gamma
Vson (m/s) : 900.11114
Molar fractions
AL 6.0290e-004
ALH 9.2486e-004
ALH2 2.8353e-005
ALH3 2.1470e-005
ALO 2.4478e-005
ALOH 5.6133e-003
AL(OH)2 3.4527e-005
AL(OH)3 3.1024e-006
AL2 1.4157e-006
AL2O 1.3669e-003
AL2O2 1.1545e-005
H 1.0276e-002
HALO 2.7342e-006
HALO2 3.5370e-007
H2 7.2954e-001
H2O 7.8723e-003
O 3.5048e-007
OH 4.1466e-005
Condensed species
AL2O3(L) 2.4364e-001
Seastead this.
C'mon, Slashdot, this is rocket science. You shouldn't need help figuring this out on your own.
I'll come out and say it: this is a stupid rocket. As Baldrson points out above, its "specific impulse" (the most important measure of a rocket fuel's usefulness) is less than a quarter that of rocket fuels currently in existence.
Aluminum is readily available on the moon, but not as big old bricks of elemental aluminum lying around. You need to *make* it by electrolyzing rock. (Don't panic, this is how we make aluminum on Earth today.) The reaction is roughly Al2O3 -> 2 Al + 1.5 O2, and oxygen is *always* a major byproduct.
Save that oxygen. You get *much* more energy burning aluminum in oxygen than you do burning aluminum in water. Estimated Isp for an aluminum-oxygen rocket is 285 -- waaay better than aluminum-ice.
Al-Ox rockets are nasty to think about, because the exhaust is a solid -- solid sandpaper, actually. But the rocket from TFA has the same problem: Baldrson's data indicates exhaust that's 1/4 alumina, 3/4 hydrogen gas.
But if water is available, and you're gonna electrolyze something to make rocket fuel, why not electrolyze water to get hydrogen and oxygen? Standard, classic, perfect rocket fuel.
Aluminum-ice has all the drawbacks of an exotic rocket fuel, and no benefits: it's not more abundant, it's not more convenient, and it sure as hell doesn't give better performance.
Aluminium is incredibly wasteful. producing it from raw materials is expensive and using recycled sources as fuel effectively reduces the overall efficiency of the aluminium economy.
This is why I suggest copper. My chemistry is too rusty to know the best stuff to replace the ice, but good enough to know that copper would make for much greener emissions.
I don't therefore I'm not.