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Space Transportation Science

New Molecule Could Lead To Better Rocket Fuel 121

Posted by Soulskill
from the rocket-science dept.
MithrandirAgain writes "Trinitramid is the name of the new molecule that may be a component in future rocket fuel. This fuel could be 20 to 30 percent more efficient in comparison with the best rocket fuels available today, according to researchers (abstract). The discovery was made at the Royal Institute of Technology (KTH) in Sweden. 'A rule of thumb is that for every ten-percent increase in efficiency for rocket fuel, the payload of the rocket can double. What's more, the molecule consists only of nitrogen and oxygen, which would make the rocket fuel environmentally friendly. This is more than can be said of today's solid rocket fuels, which entail the emission of the equivalent of 550 tons of concentrated hydrochloric acid for each launch of the space shuttle,' says Tore Brinck, professor of physical chemistry at KTH."
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New Molecule Could Lead To Better Rocket Fuel

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  • by glueball (232492) on Friday December 24, 2010 @10:19AM (#34659616)

    From TFA:
    "It remains to be seen how stable the molecule is in a solid form," says Tore Brinck.

    And until then, this is a premature press release to be criticising the shape shuttle solid rockets.

    Someone must need to re-up on their grant.

    • The scientists have also managed to produce enough of the compound in a test tube for it to be detectable.

      Yes, I would have to agree that they're jumping the boat a tad. A long ways to go to fill up a rocket.

      But the name is way cool. Kudos to the marketing team!

    • Most modern solid-fuel rockets use pretty much the same fuel as the shuttle SRBs. It's cheap, stable and reliable but it does produce a lot of goop and the ISP could be better. If this stuff is stable it might make an excellent replacement for ammonium perchlorate oxidizer.

      • by EccentricAnomaly (451326) on Friday December 24, 2010 @01:41PM (#34660836) Homepage

        Most modern solid-fuel rockets use pretty much the same fuel as the shuttle SRBs. It's cheap, stable and reliable but it does produce a lot of goop and the ISP could be better. If this stuff is stable it might make an excellent replacement for ammonium perchlorate oxidizer.

        Shuttle SRBs are more expensive and less reliable than equivalent liquid boosters. This is the main reason why SpaceX is only using liquid engines in the Falcon-9. ULA uses solid boosters for extra thrust on the Atlas V, but these solids are cheaper and more reliable than Shuttle SRBs. In addition, based on recent conference papers, I think they want to get away from solids in their next generation of rockets.

        So why is NASA planning on using boosters based on the lower performing, more expensive, and less reliable Shuttle SRBs in their new Heavy lift rocket? This is because the Utah Congressional delegation is lobbying heavily for the company that makes the SRBs. The Utah senators inserted text into the continuing resolution that NASA is currently operating under that they claim prevents NASA from even doing trade studies to consider any alternatives to using the Shuttle SRBs.

        Solids might have made sense in the 60s, but with current technology they are no longer needed except in a few specialized applications for robotic planetary exploration spacecraft.

        • Solids do have some advantages over liquids. Primarily acceleration. But for human payloads, liquid rocket engines make more sense--particularly if an accident does occur, the engines can be shut off, allowing escape rockets to take the passengers away from the rest of the rocket. This is the Ares rocket's biggest problem--there are periods of time where the escape rocket may not be able to escape the solid vehicle underneath it..
          • Liquids can be designed to have even higher acceleration (see the Sprint Anti ballistic missile). Currently built solids have high thrust/weight because they are made as boosters, not because they have inherently higher acceleration. Solids best feature is storablity in a "ready to fire" state without N2O2 or other such nastiness or cyro fuels.
        • They didn't even have an advantage in the 60s. Dr. Von Braun wouldn't even use them in any of his designs.
    • It does seem a bit early to be proclaiming this molecule as a new rocket fuel, but it's never too early to criticize the shuttle's SRB's. Not only are they ridiculously expensive and horrible for the environment, but they're terribly unsafe. Seriously, the reason why the shuttle has to be assembled vertically and towed by a huge and expensive piece of custom machinery to the launchpad is because otherwise the SRB's will probably explode.

      Now at this point you might speculate that the SRB's are esential to
      • by espiesp (1251084)

        Hey now, don't forget the Saturn V rocket either. That mother could haul some mail. With an awesome service record to boot.

  • by CrimsonAvenger (580665) on Friday December 24, 2010 @10:31AM (#34659690)

    The key part being "solid". Solid rocket fuels are notoriously inefficient compared to liquid fuels.

    From the sounds of this stuff, assuming that 20-30% is closer to 30% than to 20%, we're talking roughly 75% as efficient as Hydrogen, and somewhat less efficient still than kerosene...

    • > Solid rocket fuels are notoriously inefficient compared to liquid fuels.

      They are also notoriously simple and inexpensive.

      • by 0123456 (636235) on Friday December 24, 2010 @12:10PM (#34660302)

        They are also notoriously simple and inexpensive.

        The LOX/LH2 in the shuttle's external tank costs far less than the two SRBs on the side. It's the liquid-fuelled engines that are expensive, if you throw them away after each flight.

        • by GigsVT (208848)

          So far, recycling equipment has been a fool's errand.

          The great experiment in reusable space craft turned out to be a massive money hole, holding back space exploration to a large extent.

          • by AJWM (19027)

            The great experiment in reusable space craft turned out to be a massive money hole

            Oh? Has anyone actually tried that experiment yet?

            And no, Shuttle doesn't count: the external tanks are thrown away, the SRB's are more crash'n'salvage than reusable (take a look at what actually gets reused), and the Orbiter undergoes a major overhaul after every mission.

            There have been experimental prototypes of reusable vehicles. DC-X for example, which demonstrated successful intact launch-abort capability as well as ra

            • by KZigurs (638781)

              I think that was exactly the parents point. Shuttle was initially sold as reusable platform that will be oh so cheap once you'll average the initial cost over the projected lifetime.

              Didn't turn out that way.

  • by gmuslera (3436) on Friday December 24, 2010 @10:53AM (#34659792) Homepage Journal
    I tought that the revolutionary molecule that would help with rocket propulsion would be thiotimoline [wikipedia.org]
    • Probably. But so far we couldn't find that past component of it, maybe in the future we will.

    • by rubycodez (864176)

      Since we have over 150,000 years experience with tylium, the human race doesn't need that thiotimoline crap.

  • Are best confined to July 4th and November 5th.

    The big drawback is that once they're lit you have no control, you can't turn them off, or even throttle them down.

    • by mangu (126918)

      The big drawback is that once they're lit you have no control, you can't turn them off, or even throttle them down.

      Something I've always wondered, if one of the shuttle's SRBs fails to lit and the other one starts up, what happens?

      • Re: (Score:3, Interesting)

        by Hoi Polloi (522990)

        A quick google search and voilà!

        More advanced solid rocket motors can not only be throttled but also be extinguished and then re-ignited by controlling the nozzle geometry or through the use of vent ports.

        • by MachDelta (704883)

          Funny, a different article on wikipedia (Space Shuttle Abort Modes) claims that: "The SRBs cannot be turned off once ignited, and afterwards the shuttle is committed to take off. "

          Wikipedia is contradicting itself? Noooooooooo!! *headasplode*

          • Re:Solid rockets (Score:5, Insightful)

            by John Hasler (414242) on Friday December 24, 2010 @12:59PM (#34660620) Homepage

            > Wikipedia is contradicting itself?

            No. There are extinguishable solid-fuel rockets. The shuttle SRBs are not among them.

            • I thought all the extinguishable solid rocket motors were the hybrids-a solid propellant ignited by a liquid/gaseous oxidizer. Stop the flow of the oxidizer and the engine turns off. Hybrids are usually not grouped with pure solids. Most (or all I believe) solid propellants in use today mix and the fuel and oxidizer and just require an ignition source and then it is a self-sustaining operation,at least inside the rockets itself, which is why they can not be turned off.
              • by Yetihehe (971185)
                Advanced solid fuels may not burn good at standard pressure, but burn at working pressure. So when your engine has only one small nozzle, pressure builds up and engine works. When you open additional ports in engine bottom, pressure drops and fuel stops burning.
              • by mbessey (304651)

                Restricting the nozzle of a solid rocket usually causes it to explode, so maybe you could "throttle" it by opening the nozzle, to reduce the burn rate. You might even be able to get it to blow itself out that way, I suppose.

      • The spacecraft is clamped down until all engines are up to full power.

        • by Muad'Dave (255648)

          That's true of the main engines, but not the solids. The explosive bolts holding the shuttle to the pad are fired before the SRBs are lit.

      • by realxmp (518717)

        The big drawback is that once they're lit you have no control, you can't turn them off, or even throttle them down.

        Something I've always wondered, if one of the shuttle's SRBs fails to lit and the other one starts up, what happens?

        Even though you can't turn off the booster you can detach it and use the range safety device to self destruct it. Have a look at "Space Shuttle Abort Modes" on Wikipedia.

      • by Muad'Dave (255648)

        I recall there being a Range Safety system [wikipedia.org] that can be fired to split the SRB open, releasing the pressure. Odds are the RSO wouldn't be able to fire the charges in the 100 mS it takes to exceed load limits due to an asymmetrical SRB firing.

        • Re:Solid rockets (Score:4, Insightful)

          by 0123456 (636235) on Friday December 24, 2010 @12:15PM (#34660338)

          Odds are the RSO wouldn't be able to fire the charges in the 100 mS it takes to exceed load limits due to an asymmetrical SRB firing.

          Doesn't really matter, because everyone dies either way: the shuttle will crash and burn if it's on the pad with one SRB missing. All you have to do is ensure you destroy the SRB before it goes flying off across Florida and crashes into a bus full of nuns and orphans on their way to Disneyland.

      • by 0123456 (636235)

        Something I've always wondered, if one of the shuttle's SRBs fails to lit and the other one starts up, what happens?

        Everyone dies. And the launch pad is probably destroyed.

        This is why the SRBs have multiple (three I think) independent igniters so that only an extremely unlikely failure could make them not ignite.

      • The signal to blow the hold down bolts and light the SRB are done only through timing. There is no check to see if both SRB's are lit before blowing the hold down bolts. So if you assume all the hold down bolts blow The stack would cart wheel either into the tower or away from the tower and kill everyone on board. If the hold down bolts didn't fire they are not strong enough to restrain the thrust from one SRB so the one that was light would rip off the pad (The skirt might give way too, I'm not sure which
        • Re: (Score:3, Interesting)

          Yeah, basically. However SRMs are incredibly reliable in terms of lighting off. They are crap in many other respects, but I can't think of an instance where a vehicle launched from a pad like the shuttle had an ignition failure in an SRB.

          Basically the drill is at T - 6 the SSMEs start. At that point it is still possible to abort. Once all 3 SSMEs are running at full power the clock hits 0, something like 6 pyro igniters in each SRM fires them up, and then maybe 500ms later the hold down bolts blow.

          As for ra

          • Actually they unzip down the side of the case. They stop at the aft segment though. That's enough to release the pressure though. RSO hands are not going to be anywhere near the button unless something is going wrong. But yeah half a second at most when the decision is made-transmitting the signal and propagating it thru the system will likely take as long. And NASA calls them RSOs, but they call themselves (M)FCOs (Mission Flight Control Officers)
            • Yeah. Apparently a couple millimeter wide crack is ENOUGH, lol. Those SRMs were an abomination. Just seeing them even considering SRMs for Constellation was enough to tell me it would never fly. They really are NOT safe.

      • by Titoxd (1116095)

        The big drawback is that once they're lit you have no control, you can't turn them off, or even throttle them down.

        Something I've always wondered, if one of the shuttle's SRBs fails to lit and the other one starts up, what happens?

        At that point, you're fucked...

  • Redeeculous (Score:5, Informative)

    by Ancient_Hacker (751168) on Friday December 24, 2010 @10:59AM (#34659830)

    Rocket fuel was a big research area in the 1950's. Dozens of very good chemists spent a whole load (hundreds of millions of 1950-size dollars) trying to make better rocket fuels.

    ( One of them wrote a informative and funny book about that time and place ).

    The short summary is: Yes, you can make higher oomph rocket fuels and oxidizers with more oxygen in them.

    But a lot of the formulas are impractical as:

    (0) They were already discovered years ago, and discarded, but chemists don't like to write up their failures, and researchers don't like to read old moldy research summaries anyway.

    (1) They're waaay too expensive to make, even for military uses.

    (2) They are highly toxic, even more toxic than the widely-used hydrazines, which can kill you in several interesting ways.

    (3) They're so unstable, you have to keep them under impossible conditions, like no sound, no vibrations, no light, and under a part per million of crud in the perfectly-smooth and unscratched nickel-plated tanks.

    (4) They can't be stored for more than a day or so before the fuel or oxidizer starts decomposing itself or the tank walls.

    (5) Too many of the researchers were vaporized while handling the stuff. Literally. Truly. Completely. That tends to make it hard to find substitute researchers to continue working with the same stuff.

    (6) For military applications, you need a fuel that can be handled by raw recruits, stored for many months, be pumped quickly into not always totally clean rocket tanks, kept in those loaded rockets for days to months, and tolerate wide temperature swings. These requirements alone disqualify a large percentage of really zippy fuels and oxidizers.

    The odds are pretty high against this "new" compound being all that new, or it passing the basic requirements for fuel or oxidizer.

    • (3) They're so unstable, you have to keep them under impossible conditions, like no sound, no vibrations, no light, and under a part per million of crud in the perfectly-smooth and unscratched nickel-plated tanks.

      If you manage to create these conditions, I'm sure a lot of husbands will pay good money to have their wifes stored under such conditions during their PMS days.

    • Please name the book & author. I grew up in Huntsville then and would like to get it for my PhD dad, who spent most of his career in rocket fuel oxidizers
      • Re:Redeeculous (Score:4, Informative)

        by Anonymous Coward on Friday December 24, 2010 @12:51PM (#34660572)

        Ignition!: An informal history of liquid rocket propellants
        John D Clark, Rutgers University Press, 1972, ISBN-10: 0813507251

        If your dad worked in oxidizers, he likely knows of this book.

        http://www.amazon.com/Ignition-informal-history-liquid-propellants/dp/0813507251
        Amazing book, some of the funniest science stories I have seen published (destroyer parts and bats!, boron!, etc...) - Any scientist would appreciate this.
        Sadly, it is out of print, and copies run up to $200. I got it from my university library and scanned the whole thing.
        You can order reprints from online sources.

    • Re:Redeeculous (Score:4, Interesting)

      by Muad'Dave (255648) on Friday December 24, 2010 @12:29PM (#34660428) Homepage

      (2) They are highly toxic, even more toxic than the widely-used hydrazines, which can kill you in several interesting ways.

      (3) They're so unstable, you have to keep them under impossible conditions

      That reminds me of a hazmat situation [tobaccodocuments.org] involving pentaborane [wikipedia.org] that happened in the 80's near me. One of my best friends as exposed, died and was resuscitated several times. He suffered organ damage and lost many of his early memories.

      See also: http://www.scribd.com/doc/15062569/Pentaborane-Taming-the-Dragonpdf [scribd.com]

    • Re:Redeeculous (Score:5, Informative)

      by joe_frisch (1366229) on Friday December 24, 2010 @08:05PM (#34662840)

      Agreed. If you want really high specific impulse fuel, then mono-atomic hydrogen, or possibly metallic hydrogen have fantastic theoretical performance. Atomic hydrogen can be easily produced (as a very low density gas), the "only" problem is stabilising it as a liquid or solid.

      In reality the problem with launching to orbit is cost, and that cost is NOT dominated by fuel. As a rough estimate a saturn V used 1 million gallons of kerosine ($5M), to put 200K pounds in orbit. That is ~$25/pound. Whatever is the driving cost in space travel, it is not the cost of the fuel.

      ---Joe Frisch

      • > Whatever is the driving cost in space travel, it is not the cost of the fuel.

        No, it's the cost of the rocket. And cryogenic turbopumps are very expensive.

    • Interesting. What was the author and title of the book, or as much as you remember? Thanks!
  • Big deal (Score:5, Informative)

    by OneAhead (1495535) on Friday December 24, 2010 @11:07AM (#34659886)
    Over the decades, chemists have come up with dozens of molecular structures that would make "the perfect rocket fuel" or "the perfect explosive" (both qualities are closely related). If only they would be stable enough to prevent accidental explosions ("It remains to be seen how stable the molecule is in a solid form"). And be possible to produce in hundreds of tons ("The scientists have also managed to produce enough of the compound in a test tube for it to be detectable.") And most important of all, cheap enough to compete with existing propellants.
    Until these problems can be addressed, this "breakthrough" is just another octanitrocubane
    http://en.wikipedia.org/wiki/Octanitrocubane [wikipedia.org]
    It's a chemical tour-de-force to synthesize difficult structures like this in the first place, and in that sense, the researchers may have made a valuable contribution to the field of synthetic chemistry, but if you expect rockets with quadruple payloads based on this molecule to be lifting of by 2015, well, don't hold your breath.

    See also: http://en.wikipedia.org/wiki/2,4,6-Tris(trinitromethyl)-1,3,5-triazine [wikipedia.org]
    • by OneAhead (1495535)
      I'd like to add that the chemical structure looks more like a potential high-explosive than a potential rocket fuel (but then again, these things are difficult to predict). Moreover, high explosives for specialized purposes do not need to be available/affordable in such high amounts as rocket fuels (but they generally do require a better shelf life, which might be an issue).
    • by RockDoctor (15477)

      Until these problems can be addressed, this "breakthrough" is just another octanitrocubane.

      Awww, shucks. You beat me to it.

      But ONC looks fun to a symmetry-phile, and TNA has a similar appeal.

      I wonder what their co-polymer would look like? Hopefully, like a hole in the lab bench.

      Hmmm, by analogy with Arsenic and Phosphorus, one might hope for a N4 entity. One might also hope that, since hydrazine is so well known as a substitute for water when washing skin too delicate to take DHMO, then analogously N4H

  • A long shot (Score:4, Interesting)

    by hankwang (413283) * on Friday December 24, 2010 @11:09AM (#34659898) Homepage
    They synthesized something enough to see it in a mass spectrometer. Note that mass spectrometers need less than a nanomol or so (0.1 micrograms), and the compound was probably in a solution, mixed with a lot of other compounds.

    Then it is being speculated that (a) the synthesis can be scaled up to produce a few hundred tonnes in a cost-effective way, (b) the stuff is stable enough to not decompose explosively if you shake it too hard, and (c) can be burnt in a controlled way to make it suitable as a rocket fuel.

    A long shot. Unfortunately, it seems to be necessary nowadays to speculate about far-fetched applications in fundamental research, since the fact that a new compound consisting of just 4 nitrogen and 6 oxygen atoms is synthesized that has never been seen before, is not considered to be interesting by itself.

  • Time for Jamie and Adam to get busy on this rumor. Bwahahahaha.
  • by damburger (981828) on Friday December 24, 2010 @11:27AM (#34660026)

    By the rocket equation, mass fraction is determined by velocity and exhaust velocity is driven two things; the mass of the molecules being put out and the pressure/temperature of the combustion chamber. The latter is limited, as once you get to about 100 atmospheres and 3000K you start to run out of materials to make the combustion chamber out of. Thus, molecule mass is the real driving factor - which is why despite the truly horrific engineering problems it entails, liquid hydrogen is a highly valued rocket fuel.

    In fact, because molecular mass is so important, H2/O2 rockets are run fuel rich, sacrificing some combustion efficiency in order to leave some unburned hydrogen in the exhaust and reduce its average molecular mass.

    So it doesn't matter how much energy you can get out of this new compound. It will only spit out oxygen, nitrogen and nitrous oxides, all far more massive than the hydrogen and water vapour you get from rockets in use at the moment. Sure, breaking down this molecule in optimal conditions might yield enough energy that the reaction products would have more velocity than the exhaust of a H2/O2 rocket, but there is a reason chemists don't build rockets; these researchers aren't taking into account the kind of unobtanium combustion chamber walls you would need to utilise such an inferno.

    • So it doesn't matter how much energy you can get out of this new compound. It will only spit out oxygen, nitrogen and nitrous oxides, all far more massive than the hydrogen and water vapour you get from rockets in use at the moment.

      Many of the "rockets in use at the moment" use fuels other than hydrogen and oxygen and many are solid fuel.

      • by damburger (981828)

        And none of those other fuels has better performance that H2/O2, so whats your point?

        The are three reasons why other fuels get used at all:

        1. Lack of technology to handle liquid hydrogen

        2. Need for a rocket (or more usually a missile) to loiter

        3. Additional acceleration during the launch phase

        1 and 2 don't apply any more to new rocket development, since even Russia and China can now handle LH2 and have stopped directly deriving their launchers from missiles. With 3 chamber pressure and temperature are again

        • by John Hasler (414242) on Friday December 24, 2010 @12:26PM (#34660402) Homepage

          And none of those other fuels has better performance that H2/O2, so whats your point?

          The solid/liquid decision and the choice of fuel is a complex engineering process involving much more than picking the one with the highest ISP.

          BTW lithium-flourine-hydrogen tripropellent has an ISP of 542, versus 455 for hydrogen-oxygen. By your reasoning everyone should be using it, but in fact it has never been used.

          There is a reason they don't use TNT as rocket fuel, you know.

          Nitrogycerin mixed with nitrocellulose was used in the past, but theoretical ISP is not the only consideration. Which is my point.

          • I'd mod you up if I didn't already make other comments.
          • by damburger (981828)
            I never said specific impulse was the only choice. And if people thought they could handle Li-F-LH2 tripropellant they would, but nobody can so they don't. Not at all inconsistent with what I said.
    • by Mandrel (765308)

      By the rocket equation, mass fraction is determined by velocity and exhaust velocity is driven two things; the mass of the molecules being put out and the pressure/temperature of the combustion chamber.

      A rocket goes up because of the asymmetry between molecules being flung against the top of the reaction chamber while passing out the bottom. I know that the chaos in the chamber means that the best way to think about this is a pressure parameter rather than the direction of individual molecules. But I've always wanted to know whether you could make a rocket engine more efficient by using electromagnetic fields to orient the molecules in such a way that the chemical reactions are biased to have more reacti

      • by damburger (981828)
        I don't think that would help. The component of molecular motion perpendicular to axis of the rocket is fairly efficiently converted into momentum parallel to the axis by interaction with the nozzle. There is an 'escape cone' of molecules that don't have enough parallel momentum to actually leave the chamber at all, but they would scatter quickly into part of the momentum space that lets them.
        • by Mandrel (765308)

          Ah OK, thanks.

          I'm hung up on conservation of momentum issues, when it may not apply (inelastic collisions?).

          The nozzle probably works in the same way that sail shape allows a boat to beat upwind, and a wing's angle of attack generates lift.

    • by careysub (976506)

      By the rocket equation, mass fraction is determined by velocity and exhaust velocity is driven two things; the mass of the molecules being put out and the pressure/temperature of the combustion chamber. The latter is limited, as once you get to about 100 atmospheres and 3000K you start to run out of materials to make the combustion chamber out of. Thus, molecule mass is the real driving factor - which is why despite the truly horrific engineering problems it entails, liquid hydrogen is a highly valued rocket fuel.

      In fact, because molecular mass is so important, H2/O2 rockets are run fuel rich, sacrificing some combustion efficiency in order to leave some unburned hydrogen in the exhaust and reduce its average molecular mass.

      ...

      Similarly the Germans improved the performance of the alcohol-LOX fueled V2 by adding inert water to the alcohol. By reducing the average molecular weight of the exhaust it improved the thrust even though it reduced the energy in the fuel.

      • by damburger (981828)
        Not sure that was the intention actually; the main reason was that 1940s engineering couldn't build a combustion chamber that could withstand the heat of reaction between pure alcohol and LOx, and diluting the alcohol lowered the temperature (The actual chamber they used on the V2 was a massive, seat-of-the-pants, fudge anyhow). Lowering the carbon content of the fuel will have improved Isp certainly, but I don't believe that is why they made the choice.
        • by careysub (976506)

          Not sure that was the intention actually; the main reason was that 1940s engineering couldn't build a combustion chamber that could withstand the heat of reaction between pure alcohol and LOx, and diluting the alcohol lowered the temperature (The actual chamber they used on the V2 was a massive, seat-of-the-pants, fudge anyhow). Lowering the carbon content of the fuel will have improved Isp certainly, but I don't believe that is why they made the choice.

          "Rockets, Missiles, and Men in Space" by Willy Ley, 1968, p. 598:

          "The fuel of the V-2 was ordinary ethyl alcohol... to which enough water had been added to bring its strength down to 75 percent by volume. The reason for the addition of the water was the following: ... The combustion products of burning ethyl alcohol are CO2 and H2O, and of course the CO2 molecule is by far the heavier. By adding water to the alcohol the proportion of water molecules in the exhaust is increased and its molecular weight dep

          • by damburger (981828)
            My mistake. Seems the main reason was exhaust velocity. However, I do recall reading about the combustion chamber issue, so even with a difference of 160K it might have been an issue.
    • by Drishmung (458368)

      By the rocket equation, mass fraction is determined by velocity and exhaust velocity is driven two things; the mass of the molecules being put out and the pressure/temperature of the combustion chamber. The latter is limited, as once you get to about 100 atmospheres and 3000K you start to run out of materials to make the combustion chamber out of. Thus, molecule mass is the real driving factor - which is why despite the truly horrific engineering problems it entails, liquid hydrogen is a highly valued rocket fuel.

      At one stage apparently, they looked at Hydogen + Flourine. Most exothermic binary reactiion known? Check. Satisfactorily low reaction mass? Check.

      Of course, quite apart from the horrific problems of dealing with liquid Flourine, the issue of that light reaction mass product, and its somewhat unfriendly characteristics led to it being abandoned.

  • ...are still some some decades, if not centuries, away. Sadly. It doesn't look like current technology can provide us with the holy grail of space exploration. This experimental fuel doesn't look like the breakthrough we need.
  • How is 550 tons of Hydrochloric Acid worse that 550 tons of concentrated Nitric Acid? The greenies abandoned themselves to pseudo-science and engineering long ago.
  • by wfstanle (1188751) on Friday December 24, 2010 @01:30PM (#34660778)

    " What's more, the molecule consists only of nitrogen and oxygen, which would make the rocket fuel environmentally friendly."

    I'm not saying that the byproducts of combustion will be dangerous but just because it is composed of only nitrogen and oxygen does not automatically make it "environmentally friendly". One of the major components of smog also consists of only oxygen and nitrogen. It's nitrogen dioxide.

    • I'm not saying that the byproducts of combustion will be dangerous but just because it is composed of only nitrogen and oxygen does not automatically make it "environmentally friendly".

      No, but it makes it PR friendly.

  • by PPH (736903) on Friday December 24, 2010 @01:35PM (#34660798)

    Nitrous oxide is also made up of only Nitrogen and Oxygen. Would we want that mixed into the air we breath? The very thought has me ROTFLMAO.

  • Does it have the power of thiotimoline [wikipedia.org] ?

  • Just because it contains only N & O, doesn't mean it leaves only friendlies in the air. NxOy is the cause of many city smogs and lung problems. And O3 is also a nasty pollutant down here in the breathing zone. Hopefully ultraviolet is able to break it back down to N2 and O2 easily - then it is a friendly.

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