Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Nuclear Power: Fusion
reactions and Fusion energy
(NIF,ITER)
Dresden, 13.12.2011
Martin Rehwald
Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Outline
1. The Fusion Reaction (Conditions, Binding energy,
Lawson criterion)
2. Fusion Energy
Magnetic confinement fusion (ITER)
Inertial confinement fusion (NIF)
Martin Rehwald, 03.02.12
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
The Fusion Reaction
Nuclear fusion is a process by which two atomic nuclei join together, or "fuse", to
form a single heavier nucleus.
1
1
H
1
1
H
2
1
H e
e
0.42 MeV
e⁻
+
e⁺
2
1.02 MeV
e
+
+
+
Martin Rehwald, 03.02.12
+
e⁺
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Conditions for Nuclear Fusion
Electromagnetic Coulomb Force
Strong Interaction
•
Bind protons and neutrons together
At atomic scale it is about 100 times
stronger, than electromagnetism
Range: 1 to 3 fm (femtometer)
Nuclei repulse each other
+
Martin Rehwald, 03.02.12
+
+
+
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Coulomb barrier
Pic 1
U r =
1
4
q 1∗ q 2
r
E p= 2.3∗ 10−13 J
E=
3
kT
2
T ≈ 1010 K
Sun: 1.5*10⁷ K
Martin Rehwald, 03.02.12
¹ http://burro.cwru.edu/Academics/Astr221/StarPhys/coulomb.gif
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Quantum tunnelling
Quantum tunneling:
Particles can, with a very
small probability, tunnel
through a barrier.
Martin Rehwald, 03.02.12
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Mass defect:
Sum of mass of protons and neutrons > measured mass of reaction products
binding energy = mass defect * c²
Pic 1
Fission
Fusion
Martin Rehwald, 03.02.12
¹ http://en.wikipedia.org/wiki/File:Binding_energy_curve_-_common_isotopes.svg
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Energy density
Material
Energy Type
Energy density (MJ/Kg)
Natural gas
Chemical
36-50
Coal
Chemical
30
Hydrogen
Chemical
142
U - 235
Nuclear
90.000.000
Nuclear
627.000.000
p – p Reaction
Martin Rehwald, 03.02.12
p – p reaction :
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Other fusion reactions
2
1H
2
1H
2
1H
3
1H
2
1H
3
2 He
3
2 He
p
Martin Rehwald, 03.02.12
3
2 He
3
1
0.82 MeV
H 1.01 MeV
4
2 He
4
2 He
3
2 He
11
5B
n0 2.45 MeV
n0 3.02 MeV
3.5 MeV
n0 14.1 MeV
3.6 MeV
p 14.7 MeV
4
2 He
2 p 12.9 MeV
3 42 He 8.7 MeV
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Lawson criterion
The Lawson criterion defines the conditions needed for a fusion reactor to reach
ignition.
For D – T Reaction:
n∗
E
2∗ 1020 s/m³
n...plasma density
E ... confinement time
n≈ 1020 m ⁻ ³, E 2 s
Magnetic Confinement Fusion
Martin Rehwald, 03.02.12
n≈ 2∗ 10 31 m− 3 , E 10− 11 s
Inertial Confinement Fusion
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Fusion energy
Magnetic confinement fusion (MCF)
Pic 1
Pic 2
Martin Rehwald, 03.02.12
¹http://www.ipp.mpg.de/de/images/pic/images_bereiche/allgemein/380x265/ionen.gif
²http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/toroid.html
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Pic 3
Tokamak
Stellarator
Pic 2
Pic 1
Martin Rehwald, 03.02.12
¹http://fusionforenergy.europa.eu/understandingfusion/whatisfusion/Whatisfusion_3.jpg
²http://www.weltderphysik.de/_img/article_large/20081015_Stellarator_MPIfPlasmaphysik.jpg
³http://www.lpp.fr/IMG/jpg/tore-3.jpg
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
ITER Design
Central
Solenoid
Blanket
Module
Vacuum Vessel
Outer Intercoil
Structure
Toroidal Field Coil
Poloidal Field Coil
Martin Rehwald, 03.02.12
¹http://www.odec.ca/projects/2004/yeun4d0/public_html/Images/ITER1.jpg
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Inertial confinement fusion (ICF)
Blowoff
Martin Rehwald, 03.02.12
Compression
¹http://en.wikipedia.org/wiki/File:Inertial_confinement_fusion.svg
Burn
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Direct Drive:
Indirect Drive
•
Laser Beams are focused at the
inner site of the cylinder
Laser Beams are focused onto
the surface of the target
Laser Beam
cylindrical hohlraum made of
gold
Target
Target, filled with a
deuterium tritium (D-T)
mixture
Martin Rehwald, 03.02.12
http://www.dpg-physik.de/dpg/gliederung/fv/p/info/pix/Pellet.jpg
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Sources
• Books:
Gerthsen Physik 21. Ausgabe, Springer-Velag
Kernphysik 2.Auflage: Bethge, Walter, Wiedemann, Springer-Verlag
Teilchen und Kerne: Povh, Rith, Scholz, Zetsche
World wide Web:
http://en.wikipedia.org/wiki/Quantum_tunnelling
http://en.wikipedia.org/wiki/Nuclear_fusion
http://en.wikipedia.org/wiki/Binding_energy
http://www.dpg-physik.de/dpg/gliederung/fv/p/info/index.html
http://www2.fz-juelich.de/portal/forschung/highlights/kernfusion
http://www.ipp.mpg.de/ippcms/de/index.html
https://lasers.llnl.gov/
http://www.iter.org/

Martin Rehwald, 03.02.12
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Nuclear Power: Fusion reactions and Fusion energy (NIF,ITER)
Sources
•
Picture:
http://burro.cwru.edu/Academics/Astr221/StarPhys/coulomb.gif
http://nige.files.wordpress.com/2011/03/curve-of-binding-energy.gif
http://www.ipp.mpg.de/de/images/pic/images_bereiche/allgemein/380x265/ionen.gif
http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/toroid.html
http://www.lpp.fr/IMG/jpg/tore-3.jpg
http://fusionforenergy.europa.eu/understandingfusion/whatisfusion/Whatisfusion_3.jpg
http://www.weltderphysik.de/_img/article_large/20081015_Stellarator_MPIfPlasmaphysik.jpg
http://www.odec.ca/projects/2004/yeun4d0/public_html/Images/ITER1.jpg
http://www.dpg-physik.de/dpg/gliederung/fv/p/info/pix/Pellet.jpg
http://en.wikipedia.org/wiki/File:Binding_energy_curve_-_common_isotopes.svg
Martin Rehwald, 03.02.12
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