Feasibility of Controlled Fusion Energy [lecture - presentation slides]

415 Pages·2003·12.364 MB·English

by  D. Whyte

NEEP 536: Feasibility of Controlled
Fusion Energy
Spring semester 2003
Prof. D. Whyte
#331 ERB
[email protected]
Tel: 2-4854
NEEP 536, Spring 2003, D. Whyte
Overview: Fusion Energy
(cid:127) Why?
– To meet growing world energy demands using a safe, clean method of
producing electricity.
(cid:127) What?
– Extract net energy from controlled thermonuclear fusion of light elements
(cid:127) Who?
– International research teams of engineers and physicists.
(cid:127) Where?
– Research is worldwide (including UW-Madison)….eventual energy
source has few geographical restrictions.
(cid:127) When?
– Many feasibility issues resolved….demonstration in next decades
(cid:127) How?
– This course
NEEP 536, Spring 2003, D. Whyte
Course outline
1. Fusion reactor physics
– Fusion reactions, fuels, Coulomb collisions, power balance
2. Magnetic confinement concept
– Configurations, MHD, pressure limits, power exhaust
– Burning plasma experiments (ITER)
3. Inertial confinement concept
– Ignition physics, Rayleigh-Taylor, drivers
– National Ignition Facility
4. Electrostatic confinement concept
5. Technology of fusion
– Neutronics, tritium, activation
– MFE: plasma-surface interactions, magnets
– ICF: drivers, chambers
6. Economics and social aspects of fusion
– Cost of electricity estimates, scalings, safety
NEEP 536, Spring 2003, D. Whyte
Expected work for course
(30%)
(cid:127) 5 homework assignments
(45%)
(cid:127) Written final exam:
Friday May 16, 7:25 p.m.
(25%)
(cid:127) Paper on related topic
– Written report will be due 1 week before….
– Brief oral presentation (~15 minutes) to the class near
end of semester
– Before starting…please let me advise you on topics
NEEP 536, Spring 2003, D. Whyte
Fusion & fission: binding energy,
∆
E = m c2
NEEP 536, Spring 2003, D. Whyte
Exothermic fusion reactions of
interest
(cid:127) Hydrogenic species definitions (A=1):
– Hydrogen or p (M=1), Deuterium (M=2), Tritium (M=3)
D + T --> 4He + n + 17.6 MeV
D + D --> (50%) T + p + 4 MeV or (50%) 3He + n + 3.3 MeV
D + 3He --> 4He + p + 18.3 MeV
T + T --> 4He + 2 n + 11.3 MeV
NEEP 536, Spring 2003, D. Whyte
Exothermic fusion reactions of
interest
Fusion reaction cross sections
10
1
)
2
m
D+D = T + p
8 0.1
D+D = 3He + n
2
-
e D +T
1
( D + 3He
0.01

s
T + T
n
r
a
b
0.001
0.0001
1 10 100 1000
Particle energy (keV)
NEEP 536, Spring 2003, D. Whyte
Estimating fusion reaction rates
(cid:127) Fundamental competition: nuclear binding force vs.
repulsive Coulomb force
U
r
nucleus
repulsive
Coulomb force
r
attracting
nuclear force
NEEP 536, Spring 2003, D. Whyte
Estimating fusion reaction rates
(cid:127) Repulsive force acting on two particles
with same charge (ions here), U
r
nucleus
Z Z e2 repulsive
Coulomb force
F = 1 2 ε, dielectric const
~8.9x10-12 F/m
4πεr2
r
attracting
r Z Z e2 Z Z e2
nuclear force
∫ ∫
U ≡ F(r)dr = − 1 2 dr = 1 2
4πεr2 4πεr
∞
So for protons (taking U=0 at infinity),
r ~ 4x10-15m, e=1.6x10-19 C, we get U~5.5x10-14 J
nucleus
Or U ~ 350 keV
NEEP 536, Spring 2003, D. Whyte
Some useful units & conversions
(cid:127) 1 eV = 1.6 x 10-19 J (particle energy)
(cid:127) 1 eV ~ 104 K (describing temperatures)
(cid:127) 10 keV ~ 108 K ~ 100 million K (typical fusion T)
(cid:127) 1 unit ~ 5x1011 J (per capita energy consumption, U.S.)
(cid:127) 16 kW/per capita power consumption --> ~ 5 TW
(cid:127) 1 barn = 10-28 m2 (cross section)
(cid:127) V ~ 1.4x104 (T / M)1/2 m/s {T in eV, M in amu}
th
NEEP 536, Spring 2003, D. Whyte