[Descenterace]

Hmmmm... looking at that 'slopping liquid' idea.  So basically, you convert nuclear energy into kinetic energy, then convert the kinetic energy back into electrical potential energy, then back to kinetic energy in a different direction?  Problem: only the liquid's kinetic energy would be converted.  You would loose the kinetic energy of the container, because you'd have to use thrust to slow down the container to make the liquid 'slop'.
Consequently, why not do away with the liquid entirely?  It's just extra mass that plays no useful part, and because the energy conversions described are not 100% efficient, it actually has a negative effect.

Container and liquid are stationary.  Container accelerates, moving the magnetic coil relative to the liquid thereby generating electrical energy.  This means that there is a resistive force to the motion of the coil relative to the liquid (the accelerating force on the container must work against this force to generate power as well as giving kinetic energy to the container).  This resistive force remains in effect until the liquid is moving at the same velocity as the container.  The thrust energy has therefore been converted into:
* electrical energy in the magnetic coil
* kinetic energy in the container
* kinetic energy in the liquid

When thrust is applied in the other direction to counter the kinetic energy of the container the same thing happens again, except the kinetic energy gains in the two opposing directions cancel each other out.  This is what happens with a conventional spacecraft.  However, this one's thrust has twice generated electrical power in the magnetic coil.  Because of this, its engine has delivered more energy than a standard spacecraft.  The extra energy delivered has been converted into light and heat (as usual in a chemical rocket) and also electrical power.

So, the liquid system would have no effect whatsoever except to generate power from rocket thrust.  There are more efficient ways of producing electricity from the chemical energy in rocket fuel.

Nice try, though.  Took me some time to spot the flaw.  The trick is to remember that energy is always conserved.  If you think you're getting something for nothing, go through the energy equation with vector quantities, not scalars.

[Flaser]

Actually it doesn't work at all and never should.

Thank you for your comments Descenterace.
I was a fool to have thought so in the begining: all inertial system's original impulse must remain the same if only internal forces are acting.

So there's no way a system inside the craft would change its momentum without expelling something.

BTW if you used nuclear engines and only nozzles to balance the craft, that way you wouldn't need any machinery except a couple of valves for the additional thrusters.

You're right about one thing: the flight model of FS hasn't nothing to do with reality.

(I did have an explanation for shields as well, I thought it was a very thin subspace layer around the craft, that made projectiles and radiation steer-off the craft. But, still I wonder how the radio works...)

[Solatar]

That would explain why shields don't work in subspace.

[Flaser]

BTW, could you tell me what exactly is an MHD genarator Descenterace?

[Solatar]

*throws in a random solution*

Maybe the engines somehow create an area of intense gravity and bend space-time and that somehow propels the ship forward? Once the distortion is turned off, the ship slowly stops bending space time and the ship is slowed (without a warped "bump" pushing the ship, there is not thrust). Ships turn by manipulating this bump in space time, or something like that.



Ok...go back to the fusion drives and inertial dampeners...

[Atlur]

Originally posted by Descenterace
And finally: Atlur, I understood exactly what you meant by 'inside the torus', but I can't think of any reason for having moving parts anywhere near a Fusion torus except for fuel insertion.  The whole point of Fusion is that it's mostly solid-state.  Magnetohydrodynamics replaces the old coolant-and-turbine system, the reaction is self-controlled, and containment is achieved with a big electromagnet.

Cold Fusion is a common source of confusion.  Fusion reactions require temperatures of 10 million degrees C, but the word 'temperature' always seems to confuse.  Temperature is simply atomic energy, and hence a vaccuum is not at absolute zero because it has no particles in it to which the term 'temperature' can be applied.  The plasma in a Fusion torus is extremely low-density.  The ions in it are at very high energies, but the total energy is low.  If you put your hand in it (disregarding radiation damage), then the plasma would come down to body temperature without raising the temperature of your hand noticably.  'Hot' nuclear reactions, such as the bog-standard Fission we're all used to, generate massive amounts of heat energy which is transferred to some sort of coolant which drives turbines.  This means lots of shielding, and lots of wasted energy.  

Magnetohydrodynamic generation is more efficient then the conventional coolant-turbine approach when electrical power is your only goal, but what about when the purpose of the reactor is to ionize a propellant? Wouldn't the energy radiated from trapped fusion products be more effective in superheating a propellant than electrical energy from a MHD generator?

[Descenterace]

Fusion, hot or cold, generates little radiation.  If you're trying to ionise a propellant, use nuclear Fission.  Uranium fuel can be synthesised from Thorium-232, which is one of the more abundant dense elements in space.

MHD works on the idea that electric current is just a moving charge.  In a transformer, a changing EMF in a primary coil induces a changing EMF in a secondary coil.
The plasma in a toroidal Fusion reactor has an electric current flowing in it.  I'm not exactly certain of the dynamics of plasma, or why this current is an alternating current, but this ring of plasma can be treated as a transformer's primary coil.  The secondary coil of the MHD generator-transformer is wrapped vertically, so the wires run parallel to the plasma.  The current in the plasma induces an EMF in the coil, generating power.

Because the plasma is only a single 'turn' coil, the current generated is low.  Typically, the voltage is low as well.  It is likely that many small torii, each about 2 metres in diameter, would be stacked up in towers like the cells in a voltaic pile.

[Darkage]

The GTVA fleet is powerd by C++ code and doesn't need to be refueld, upgrades of engines/weapon systems/targeting systems etc are done by patches that you download or by using the launcher:p




*runs*

[Tiara]

Originally posted by Darkage
The GTVA fleet is powerd by C++ code and doesn't need to be refueld, upgrades of engines/weapon systems/targeting systems etc are done by patches that you download or by using the launcher:p

:ha:

[Flaser]

Originally posted by Atlur


Magnetohydrodynamic generation is more efficient then the conventional coolant-turbine approach when electrical power is your only goal, but what about when the purpose of the reactor is to ionize a propellant? Wouldn't the energy radiated from trapped fusion products be more effective in superheating a propellant than electrical energy from a MHD generator?

That's what I proposed in the first space.

However Descenterace commen once again struck a nerv, for I have to admit he has superioir knowledge of fusion compared to me.

However I do have one doubt: how come a fusion reaction creates so little radiation? After all the sun works the sae way

The reason I thought of a fusion nuclear drive was, that the fusion reactor is quite clean, while it still produces an enormous ammount of power.

[Descenterace]

In Fusion reactions, more energy is released per escaped neutron.  In Fission, a very large number of neutrons escape the material compared to the amount of energy produced.

Most of my physics knowledge is the result of weapons design projects.  Such as the Ion Cannon I designed when I was in Secondary school.  And the Railgun I designed about seven months ago.
OK, so these projects would never work, but you can learn a lot by doing things like this.  Like why they don't work.  Oh, and I read a load of Quantum Physics stuff too, and it's crystal clear to me...  where people go wrong is trying to imagine quantum particles as objects.  Because Quantum Theory is maths, these particles can only be described in terms of how they interact with each other.  So it is possible to understand Quantum Physics without being confused by it.

[Flaser]

Per escaped neutron?

I understand what escaped neutron means, however I don't understand than what's the problem. In this case its not the reaction's waster radiation that I'd like to use.

Is it possible to use a fusion reactor for a nuclear drive?

[Descenterace]

In a nuclear reaction, atoms break up or join to produce new atoms and free neutrons.  These neutrons usually go on to trigger (and take part in) further atom-smasing/combining.  Neutron radiation is comprised of neutrons that escape the material instead of being absorbed in a reaction.
The only radiation you can use is the waste radiation.  The rest is consumed in the reaction.

Unless you're using a 'hot' fusion reaction, in which case the 10 million degrees C plasma temperature becomes VERY significant, I don't think it would be possible to build a Fusion-based nuclear drive.  The Fission-based nuclear drive involves a big cylinder of Boron with holes drilled through it, leading to a parabolic combustion chamber/thruster.  Water with dissolved Uranuim salts is pumped through the Boron block into the thruster, where the Uranium eventually exceeds critical mass and creates a slow nuclear explosion.  This reaction is far more violent than in a power station, and is only kept in check by the rate of fuel flow and the Boron block.  Basically, a nuclear drive involves detonating a stream of small A-bombs behind the ship.

[Flaser]

Originally posted by Descenterace
In a nuclear reaction, atoms break up or join to produce new atoms and free neutrons.  These neutrons usually go on to trigger (and take part in) further atom-smasing/combining.  Neutron radiation is comprised of neutrons that escape the material instead of being absorbed in a reaction.
The only radiation you can use is the waste radiation.  The rest is consumed in the reaction.

Unless you're using a 'hot' fusion reaction, in which case the 10 million degrees C plasma temperature becomes VERY significant, I don't think it would be possible to build a Fusion-based nuclear drive.  The Fission-based nuclear drive involves a big cylinder of Boron with holes drilled through it, leading to a parabolic combustion chamber/thruster.  Water with dissolved Uranuim salts is pumped through the Boron block into the thruster, where the Uranium eventually exceeds critical mass and creates a slow nuclear explosion.  This reaction is far more violent than in a power station, and is only kept in check by the rate of fuel flow and the Boron block.  Basically, a nuclear drive involves detonating a stream of small A-bombs behind the ship.

http://pwg.gsfc.nasa.gov/stargaze/Snucfly.htm

I suggest you take a look at the link above.

What you say is apropiate, but not a 100% true.
IIRC the first nuclear drive to be devised simply used the heat from the reactor to accelerate the propellant agent.
Then there was project Orion which indeed works as you described, however that project is lot more hideous and dangerous than the original idea.

My FS engine uses the first system, so it's not the reaction itself that propels the craft.
I always thought in a "hot" reaction as you put it, however I have my doubts now.
There are a lot of rumors about cold fusion - you've enlightened me, so know I don't necessarly think only of the meson catalysed humbug that the science community had to stomach about 10 years ago.