AAWSAP DIRD, Aneutronic Fusion Propulsion I, November 2010

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UNCLASSIFIED/ /PO lt Offl@IAL WS& &NkY
i2D + i3T ➔ 01n [14.1 MeV] + 24He [3.5 MeV]
i2D + /D ➔ 0 1n [2.45 MeV] + 23He [0.82 MeV]
i3T + i3T ➔ 2 x o1n + 24He + [11.3 MeV split between the neutrons and helium]
Figure 7. Low Temperature Fusion Reactions.
l E+-OJ ----------------------­
1.E+OO +-----1-------'---------,....-----+----+-­
, 1
-
- D-T
...
,,,,
-
D·D
,,,,
,,,,
-
• D-He3
1.E--01 +-----+-----+----------+------+-­
I
C !
~
C
0
-·­
~ 1.E-02
e
~
V
1.E-04 -~ --+-----1_,_______________
1
l .E-0.5 ,.___.__
I
I
· '
. ,,,,
,,,,
"
I,.,, .
I
-
20
40
60
80
100
Deuteron Energy(keVI
Figure 8. Fusion Ignition Energies for D-T, D-D, and D-He3.
Figure 8 shows the probabilities of these reactions occurring, expressed in units of
barns (1 b = 10-28 m2). The D-T reaction becomes increasingly probable as the energy
of the deuterium nucleus (deuteron) reaches about 5 keV. In terms of temperature,
this equals about 10 million degrees kelvin. At 10 keV (100 million degrees kelvin), the
two D-D reactions listed in Figure 7 become more probable and D-He3 fusion becomes
viable at 30 keV (300 million degrees kelvin). There are several ways to achieve these
temperatures in a controlled manner. For example, Edward Teller and Stanislaw Ulam
developed a design for a fusion, or thermonuclear bomb, that used a plutonium fission
atomic bomb to reach the ignition temperature for fusion. Deuterium is the most useful
fuel for low-temperature fusion reactors, and there is a limitless supply available by
centrifuging ordinary tap water to separate out heavy water (D2O).
Because of deuterium's availability, a strong incentive exists to develop manageable
ways to initiate nuclear fusion, concentrating on the fusion schemes outlined in Figure 6;
UNCLASSIFIED/fF&A &FFI&I:.l.k W&li &NkY
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