Does anyone have any idea what the required temperatures in the
chambers of these fusion rockets would be (I'm not intending to fan
fthe flamewar, I've tried this before, and my answers allways stink)
I tried using the kinetic theory of gasses to get a figure for the
temperature. Somebody tell me if I'm wrong:
First F=ma
Assume a 100t spaceship weighs 100 metric tons (10^5 kg) (no way, it's
a lot more than that, but bear with me). a = 10m/s^2 (1 g more or
less) Thus F = 10^6N
F = dp/dt (change in momenum w.r.t time)
dp/dt = dm/dt (mass of gas expelled per second) V (speed of gas
molecules)
From an earlier post dm/dt = 500 g/s = .5 kg/s
Thus 10^6N = 0.5 kg/s * 2*10^6m/s
inother words the rocket exhaust to be "non-reactionless" has to be
traveling at 2 million meters a second (2/3 % of the speed of light).
According to the kinetic theory of gasses V = (RT/M)^.5 where R is the
gas constant (8 J/mol K) T is the temperature and M the molecular mass
of the gas. Thus, T = (V^2)*(M/R). M = .001 kg/mol, r=8 , M/R ~ 10^-4
this means if V=10^6 then V^2=10^12 and T must be on the order of 100
MILLION degrees.
Even if this is kept in a magnetic bottle, it's black body radiation
will melt anything. The peak frequency in the blackbody distribution
is at 10^20 Hz at that temperature. The wavelength is on the order of
a hundreth of an angstrom (well into the X-Ray region).
This seems a *bit* odd to me, could someone please check my physics (I
will admit to using some simplyfying assumptions that could introduce
errors in my calculations, generally I tried to err on the side of
conservativism. But even if I'm off by _4 orders of magnitude_ we
need temperatures ten times what is found on the surfaces of the
hottest stars.
To be honest, if I'm right, I prefer the thruster plates. They make
much more sense. Somebody tell me what I did wrong.
-Love, Kisses, and a Neutron Bomb
-Eric the Finn