quote:Posteth Timo: I think the first pic is closer to what I'd like to see inside the ship. The big deuterium tank atop the secondary hull would be consistent with TNG, but as said, TOS tech could well be different in some ways. Coal boilers vs oil-burning engines, or something - both use pistons to translate the expansion of gases created by burning fuel into rotary movement, but the setup within the ship is drastically different.
This might be a topical point to post the following, a rather whimsical essay I tossed off on the Kobayashi Maru and neutronic fuel. For which I would be pleased to receive critical review and constructive criticism.
quote:What The Heck Is The Kobiyashi Maru Hauling? Neutronic Fuel And Why Movie-era Ships Don�t Have Big Dueterium Tanks
If you remember your high school chemistry you know that atoms consist of an equal number of protons and electrons, and (usually) some neutrons as well. Protons have a positive charge. Electrons have a negative charge. Neutrons have no charge, but have almost as much mass as protons. You may also know that the difference between matter and antimatter is polarity: antiprotons have a negative charge, and antielectrons have a positive charge. Anti-electrons have been produced in lab experiments; they are called positrons (yes, Data has antimatter for brains. Are you surprised?)
Suppose that �neutronic fuel� is just what it sounds like: free neutrons. I imagine the advantage of neutronic fuel is density. The Constitution (refit) class starship has a much smaller fuel tank, relative to the ship�s overall size, than the huge balloon that holds the Enterprise-D�s dueterium. Mind you, this is off-the-cuff amateur physics, but a neutron star is the size of Chicago. Even if 23rd-century technology can�t achieve that degree of density, there�s still a lot of bang for your bunkerage.
The existance of �antineutrons� in the Star Trek universe is also established in Star Trek IV, when Spock is challenged by a computer test to �adjust a sine wave�s magnetic envelope so that antineutrons can pass through it but antigravitons cannot.�
The disadvantage? Real life chemistry provides the answer: �free neutrons have great penetrating capabilities and are highly damaging to living tissue.� This stuff is dangerous! And a lot harder to keep contained than mere cryogenic liquid. No wonder those guys wore rad suits. TNG-era starships are bigger, and probably built of lighter, stronger materials, so they can afford the greater volume penalty of using deuterium for the sake of increased safety.
The situation is analagous to atmosphere in modern spacecraft. NASA has always used partial-pressure atmospheres of pure oxygen in its spacecraft, eliminating the mass of the inert nitrogen present in Earth�s atmosphere. Pressures in spacesuits are even lower. The disadvantage is the need to decompress�adjust to the lower pressure. Which may be fine for highly trained professionals, but once we no longer need to save every gram of mass, it would be wise to add some nitro to the mix and equalize the pressure. Otherwise you might have a real incident like the one in Ben Bova�s novel Moonrise, where an astronaut in a decompressing moonbase scrambles into a spacesuit to breathe�and promptly dies of an embolism.
Spotted the problem yet? If the difference between matter and antimatter is the reversed electrical charge, and neutrons have no charge, how can there be antineutrons? Beats me, but gravitons don�t exist either. Maybe in the next 200 years advances in the understanding of physics will make the definition of antimatter more complex. After all, if you don�t know anything about intersexuality or gender dysphoria, gender and biological sex seem like simple either/or propositions too.
(I postulate that early Starfleet ships also used dueterium, because the technology (and possibly the physics) needed for nuetronic fuels did not exist yet. This situation may have obtained into the TOS era, since I have only seen neutronic fuel mentioned in movie-era sources. On the other hand, antineutrons might be used to explain the exaggerations of antimatter�s explosive power which some TOS episodes are guilty of. See http://www.ditl.org/index.htm?list=/listarticles.htm for details of the problem.)
posted
Fusion reactors over antimatter for power. No way. I believe the idea in the TMP impulse engine was that it what's sometimes called an "antimatter annihilation engine", in which antiprotons are slammed intro deuterium and the resulting enegy is directed by a magnetic field out an exhaust port. The refit supposedly had fushion reactors for backup, that would burn deuterium alone. Since a matter-antimatter explosion is just about as 100% fuel efficient as you can get, it's doubtful it would be "replaced" by pokey old fusion.
-------------------- "Well, I mean, it's generally understood that, of all of the people in the world, Mike Nelson is the best." -- ULTRA MAGNUS, steadfast in curmudgeon
Registered: Feb 2001
| IP: Logged
posted
Also remember that the 'Kobiyashi Maru Scenario dates back to Kirk's Academy days, so it follows that the use of Neutronic fuel is at least as old. That doesn't necessarily mean that Starfleet ships have ever used that fuel source though, given that the Kobiyashi Maru was a civilian ship it could easily have been transporting Neutronic fuel for a non-starfleet client. It's possible that NF is a popular alternative fuel for commercial ships or unmanned vessles.
Also I think I've heard another definition of NF as being a special variety of Deuterium, I don't recall exactly how it's different, maybe the Deuterium atoms have an extra Neutron or something.
posted
From the very little non-Trek results Google returns, it seems that 'neutronic fuel' is sometimes (although very very rarely) used to describe tritium in the context of deuterium-tritium fusion reactions, apparenty because this reaction releases energized neutrons (radioactivity).
Since we know Starfleet uses deuterium for it's M/AM and fusion reactions, they might also need tritium for the impulse engines. Although tritium is nasty artificial radioactive stuff.
(BTW, the only time tritium is mentioned on DS9 and TNG is here. Klingons use tritium in their warp cores, apperently).
quote:Originally posted by MarianLH: Spotted the problem yet? If the difference between matter and antimatter is the reversed electrical charge, and neutrons have no charge, how can there be antineutrons?
It's not that simple. I did a short google search and came up with this:
quote:In the case of a neutron, you are very much right, the charge cannot be opposite, since it does not have a charge. The trick is however, that the neutron is not an ELEMENTARY particle!!!
It is made from 3 other smaller particles, called QUARKS! Namely, the neutron is made out of one quark called Up quark and two quarks called Down quarks. ( just for reference, the proton is made out of two Up quarks and one Down quark). These quarks HAVE CHARGE!!! The charge of the Up is +2/3*1.606*10^-19 C and the charge of the Down is -1/3*1.606*10^-19 C. ( That way you can see, the neutron is really neutral and the proton has really charge +1.606*10^-19 C )
Now, the antineutron, is made out of one ANTI Up ( which has a charge -2/3*1.606*10^-19 C and two ANTI Downs ( each of them having a charge +1/3*1.606*10^-19 C), and that makes him very different from a neutron.
quote:Originally posted by MrNeutron: Fusion reactors over antimatter for power. No way. I believe the idea in the TMP impulse engine was that it what's sometimes called an "antimatter annihilation engine", in which antiprotons are slammed intro deuterium and the resulting enegy is directed by a magnetic field out an exhaust port. The refit supposedly had fushion reactors for backup, that would burn deuterium alone. Since a matter-antimatter explosion is just about as 100% fuel efficient as you can get, it's doubtful it would be "replaced" by pokey old fusion.
I think you must have misunderstood me. I never said anything about fusion. I'm describing a matter-antimatter reaction using neutrons/antineutrons as opposed to deuterium/anti deuterium. I apologise if that wasn't clear.
I too think the movie-era impulse drive was a variation on an antimatter rocket, although I imagined it as being more like an old-style Sanger rocket, which wouldn't require any fuel other than the matter/antimatter reactants. Since starships at impulse must cheat Newton somehow regardless, the limitations of Dr. Sanger's original design would not necessarily be a problem.
You're quite right about the backup fusion reactors needing a fuel supply though.
quote:Originally posted by Reverend: Also remember that the 'Kobiyashi Maru Scenario dates back to Kirk's Academy days, so it follows that the use of Neutronic fuel is at least as old.
Good argument. Although there is a counterargument, that there's no reason why the details of the test can't vary over time. Maybe when Kirk took the test the Kobayashi Maru was hauling deuterium. Or maybe cobalt, for all we know. =)
Certainly there are other possible explanations of what neutronic fuel is and what it's used for, and I'm sorry if I suggested otherwise. I'm not messianic about my interpretations of Treknology. It's just a theory.
quote:Originally posted by B.J.: It's not that simple. I did a short google search and came up with this:
quote:In the case of a neutron, you are very much right, the charge cannot be opposite, since it does not have a charge. The trick is however, that the neutron is not an ELEMENTARY particle!!!
It is made from 3 other smaller particles, called QUARKS! Namely, the neutron is made out of one quark called Up quark and two quarks called Down quarks. ( just for reference, the proton is made out of two Up quarks and one Down quark). These quarks HAVE CHARGE!!! The charge of the Up is +2/3*1.606*10^-19 C and the charge of the Down is -1/3*1.606*10^-19 C. ( That way you can see, the neutron is really neutral and the proton has really charge +1.606*10^-19 C )
Now, the antineutron, is made out of one ANTI Up ( which has a charge -2/3*1.606*10^-19 C and two ANTI Downs ( each of them having a charge +1/3*1.606*10^-19 C), and that makes him very different from a neutron.
posted
Re: Harry's terminology point: The term "neutronic" makes a lot of sense in connection with fusionables such as deuterium and tritium. After all, basic hydrogen could also be used as fusion fuel; there could well be a practical need to distinguish it from the hydrogen isotopes that are "neutronic", that is, have one or two neutrons in addition to the obligatory proton.
Fanfic speaks of different fuel types, with deuterium-tritium fusion in use during TOS and deuterium-deuterium fusion taking over later on. Similarly, TNG speaks of different kinds of lithium crystals (di-, para-, tri-) with different properties and applications. Different types of transport ships might be needed for the different commodities, and thus complex terminology might emerge. And today, we have LNG tankers for hauling liquid natural gas, but we don't have tankers that would haul non-liquid natural gas. The letter L appears superfluous here... "Neutronic" could be just as superfluous in Trek.
posted
Maybe 'Neutronic' referes to the state that the fuel is shipped in.
-------------------- joH'a' 'oH wIj DevwI' jIH DIchDaq Hutlh pagh (some days it's just not worth chewing through the leather straps in the morning) The Woozle!
Registered: Nov 2002
| IP: Logged
Printer-friendly view of this topic
