A frozen slurry of nano-sized aluminum powder and water ice makes a pretty fair rocket. Whoda thunk it? Actually appears to work quite well; aluminum will reduce water to hot hydrogen and aluminum oxide, which should have a good Isp with fewer nasty components than the standard solid rocket fuel formula that uses ammonium perchlorate and synthetic rubber binder.
Suggested as a basis for in-situ rocket propulsion. Almost as nifty as paraffin-based hybrid rockets.
> A frozen slurry of nano-sized aluminum powder and water ice makes a > pretty fair rocket. Whoda thunk it? Actually appears to work quite > well; aluminum will reduce water to hot hydrogen and aluminum oxide, > which should have a good Isp with fewer nasty components than the > standard solid rocket fuel formula that uses ammonium perchlorate > and synthetic rubber binder.
> Suggested as a basis for in-situ rocket propulsion. Almost as > nifty as paraffin-based hybrid rockets.
High energy oxidation of either pure powered aluminum or titanium in contact with pure oxygen could indeed generate a high specific impulse in regards to a rocket's efficiency, but I'm keen to see how you get the ground metallic fuel to the combustion chamber in a non-fluid form.
> > A frozen slurry of nano-sized aluminum powder and water ice makes a > > pretty fair rocket. Whoda thunk it? Actually appears to work quite > > well; aluminum will reduce water to hot hydrogen and aluminum oxide, > > which should have a good Isp with fewer nasty components than the > > standard solid rocket fuel formula that uses ammonium perchlorate > > and synthetic rubber binder.
> > Suggested as a basis for in-situ rocket propulsion. Almost as > > nifty as paraffin-based hybrid rockets.
> > --Damon
> "Theoretically, ALICE can be manufactured in distant places like the > moon or Mars, instead of being transported to distant locations at high > cost."
> Yup. Plenty of water on the moon and Mars.
Depending on where you try to extract it, there might be more than enough, yes.
>> A frozen slurry of nano-sized aluminum powder and water ice makes a >> pretty fair rocket. Whoda thunk it? Actually appears to work quite >> well; aluminum will reduce water to hot hydrogen and aluminum oxide, >> which should have a good Isp with fewer nasty components than the >> standard solid rocket fuel formula that uses ammonium perchlorate >> and synthetic rubber binder.
>> Suggested as a basis for in-situ rocket propulsion. Almost as >> nifty as paraffin-based hybrid rockets.
> High energy oxidation of either pure powered aluminum or titanium in > contact with pure oxygen could indeed generate a high specific impulse > in regards to a rocket's efficiency, but I'm keen to see how you get > the ground metallic fuel to the combustion chamber in a non-fluid > form.
Not to mention slag formation in the combustion chamber. In a solid fuel propellant grain, the slag would be blown out promptly (except that some seems to puddle around the nozzle flex joint).
It's amusing to me to think of water as an oxidizer, but it emphasizes how energetic burning aluminum (and other metals) can be, stripping the oxygen from hydrogen ash with lots of excess energy, which in turn gets the copious hydrogen really hot.
Now if I could just find out what the expected vacuum Isp would be... Upper stage motors based on this chemistry might have compelling advantages, despite the inconvenience of having to keep them frozen.
And I am reminded that aluminum is an important component of modern high energy explosives; nano aluminum would only be an improvement in the energy yield. I suspect the production and distribution of the stuff will be closely monitored.
> >>> A frozen slurry of nano-sized aluminum powder and water ice makes a > >>> pretty fair rocket. Whoda thunk it? Actually appears to work quite > >>> well; aluminum will reduce water to hot hydrogen and aluminum oxide, > >>> which should have a good Isp with fewer nasty components than the > >>> standard solid rocket fuel formula that uses ammonium perchlorate > >>> and synthetic rubber binder.
> >>> Suggested as a basis for in-situ rocket propulsion. Almost as > >>> nifty as paraffin-based hybrid rockets.
> >>> --Damon
> >> "Theoretically, ALICE can be manufactured in distant places like the > >> moon or Mars, instead of being transported to distant locations at high > >> cost."
> >> Yup. Plenty of water on the moon and Mars.
> > Depending on where you try to extract it, there might be more than > > enough, yes.
> I'm not aware that water in any quantity has been found on the moon.
Definitely located on Mars. The jury's not in yet on the moon, which is why the "might be".
It's not yet certain that there isn't any there, and some evidence for it.
> Pat Flannery <flan...@daktel.com> wrote: > :Damon Hill wrote:
> :>http://rocketdungeon.blogspot.com/2009/08/future-of-solid-propellant- > :> oxidizers.html > :> > :> A frozen slurry of nano-sized aluminum powder and water ice makes a > :> pretty fair rocket. Whoda thunk it? Actually appears to work quite > :> well; aluminum will reduce water to hot hydrogen and aluminum oxide, > :> which should have a good Isp with fewer nasty components than the > :> standard solid rocket fuel formula that uses ammonium perchlorate > :> and synthetic rubber binder. > :> > :> Suggested as a basis for in-situ rocket propulsion. Almost as > :> nifty as paraffin-based hybrid rockets. > : > :High energy oxidation of either pure powered aluminum or titanium in > :contact with pure oxygen could indeed generate a high specific impulse > :in regards to a rocket's efficiency, but I'm keen to see how you get the > :ground metallic fuel to the combustion chamber in a non-fluid form. > :
> I believe what's being talked about is a SOLID rocket motor, Pat. You > get the ground metallic fuel to the combustion chamber the same way > you get the ammonium perchlorate to the combustion chamber in a SRB.
> Alternatively, it seems to me that if you ground the metal fine enough > you could use 'powder' injectors, as it would behave much like a > fluid.
They described the original mixture as being like toothpaste.
This means that if it does not act like a non-Newtonian fluid that it will flow under pressure.
So if instead of freezing the mixture they just (Ha, ha, ha - 'JUST' I said as if it would be easy) feed this mixture into the combustion chamber with extra oxygen and/or water also injected you should have an interesting rocket design.
Earl_Colby_Pottinger <earlcolby.pottin...@sympatico.ca> wrote: >They described the original mixture as being like toothpaste.
>This means that if it does not act like a non-Newtonian fluid that it >will flow under pressure.
>So if instead of freezing the mixture they just (Ha, ha, ha - 'JUST' I >said as if it would be easy) feed this mixture into the combustion >chamber with extra oxygen and/or water also injected you should have >an interesting rocket design.
There was a guy I saw somewhere recently who was seriously proposing to save on booster weight by using a fuel with 'the consistency of a stick of chewing gun' - and feeding it from a drum on the ground to the booster inflight.
Looked pretty energetic to me, though it also produces a lot of slag (molten aluminum oxide). Given there's lot of really hot hydrogen released, wonder if this could be used to augment thrust with atmospheric oxygen?
> There was a guy I saw somewhere recently who was seriously proposing > to save on booster weight by using a fuel with 'the consistency of a > stick of chewing gun' - and feeding it from a drum on the ground to > the booster inflight.
That ranks right up there with Korolev's minishuttle that was going to be pulled skyward via a cable attached to the tail end of the core stage of a R-7. How exactly are you supposed to keep the fuel stick from being ignited by the exhaust of the ascending rocket as it is wound up into it?
> Looked pretty energetic to me, though it also produces a lot of > slag (molten aluminum oxide). Given there's lot of really > hot hydrogen released, wonder if this could be used to augment > thrust with atmospheric oxygen?
Ah-ha! The plot thickens! From the Aviation Week "Blackstar" article (page 4 again):
"The orbiter's belly appears to be contoured with channels, riblets or 'strakelets' that direct airflow to engine inlets and help dissipate aerodynamic heating. These shallow channels may direct air to a complex system of internal, advanced composite-material ducts, according to an engineer who says he helped build one version of the orbiter in the early 1990s. Air is directed to what is believed to be aerospike engines similar to those once planned for use on the NASA/Lockheed Martin X-33."
Derek Lyons wrote: > There was a guy I saw somewhere recently who was seriously > proposing to save on booster weight by using a fuel with 'the > consistency of a stick of chewing gun' - and feeding it from a > drum on the ground to the booster inflight.
>> There was a guy I saw somewhere recently who was seriously >> proposing to save on booster weight by using a fuel with 'the >> consistency of a stick of chewing gun' - and feeding it from a >> drum on the ground to the booster inflight.
Pat Flannery <flan...@daktel.com> wrote: >Derek Lyons wrote:
>> There was a guy I saw somewhere recently who was seriously proposing >> to save on booster weight by using a fuel with 'the consistency of a >> stick of chewing gun' - and feeding it from a drum on the ground to >> the booster inflight.
>That ranks right up there with Korolev's minishuttle that was going to >be pulled skyward via a cable attached to the tail end of the core stage >of a R-7.
As a general rule, there are damm few alt.launch techs so outright batshit crazy that there isn't *someone* (otherwise reasonable) who will champion it.
>How exactly are you supposed to keep the fuel stick from being ignited >by the exhaust of the ascending rocket as it is wound up into it?
IIRC handwavium and flying the booster at such an angle that the exhaust didn't impinge on the fuel stick. I.E. don't ask me to defend it, I merely report it... :)
Jim Davis <jimdav...@earthlink.net> wrote: >Derek Lyons wrote:
>> There was a guy I saw somewhere recently who was seriously >> proposing to save on booster weight by using a fuel with 'the >> consistency of a stick of chewing gun' - and feeding it from a >> drum on the ground to the booster inflight.
Pat Flannery wrote: >>> http://www.universaltransportsystems.com > The sound of the fuel strip coming off of the reel at Mach 20+ > is really going to be something to hear. :D
In all fairness, Pat, their plan calls for the fuel ribbon to be completely unwound while still at (relatively) low speeds. Then the (very long) fuel ribbon trailing behind the craft will be steadily wound in and consumed as the vehicle accelerates.
But I think their chances of success lie somewhere between microscopic and none.
>> There was a guy I saw somewhere recently who was seriously >> proposing to save on booster weight by using a fuel with 'the >> consistency of a stick of chewing gun' - and feeding it from a >> drum on the ground to the booster inflight.
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