This book deals with the specific contact between the fourth state of matter, i.e. plasma, and the first state of matter, i.e. a solid wall, in controlled fusion experiments. A comprehensive analysis of the main processes of plasma-surface interaction is given together with an assessment of the most critical questions within the context of general criteria and operation limits. It also contains a survey on other important aspects in nuclear fusion.
Author(s): D. Naujoks
Edition: 1
Year: 2006
Language: English
Pages: 292
Tags: Физика;Физика плазмы;
Contents......Page 9
1 Introduction......Page 13
Part I: Fusion as Energy Source......Page 15
2 Energy Problem and Related Safety Aspects......Page 16
3.1 Fusion Reactions......Page 19
3.2 Ignition and Burn Criteria......Page 22
4.1 Inertial Plasma Confinement......Page 28
4.3 Stellarator Concept......Page 29
4.4 Tokamak Concept......Page 31
4.5 Design of the First Wall......Page 32
Part II: The Plasma-Material Interface......Page 38
5 The Plasma State......Page 39
5.1 Ionization Degree and Coupling Constant......Page 40
5.2 Debye Length......Page 42
5.3 Plasma Frequency......Page 43
5.4 Collisions in Plasmas......Page 44
5.5 Transport Processes in Plasmas......Page 49
5.6 The Vlasov Equation......Page 53
5.7 The Poisson Equation......Page 54
6 Particle Coupling......Page 58
6.1 Binary Collisions......Page 59
6.2 Particle Transport in Matter......Page 72
6.3 Material Modification by Ion Beams......Page 81
6.4 Retention and Tritium Inventory Control......Page 84
6.5 Impurity Generation......Page 85
6.6 Charge Effects......Page 97
6.7 Diffusion-Controlled Sputtering......Page 98
6.8 Backscattering......Page 100
6.9 Electron Emission......Page 105
6.10 Modeling of Particle–Solid Interaction......Page 109
7 Electrical Coupling......Page 115
7.1 Electron Flux Density......Page 116
7.2 Ion Flux Density......Page 117
7.3 Bohm Criterion with the “=” Sign......Page 118
7.4 Space Charge Limited Currents......Page 122
7.5 Effect of Magnetic Field Geometry......Page 124
7.6 Modeling of the Electric Sheath......Page 126
8.1 Heat Flux Densities......Page 133
8.2 Change of Surface Temperature......Page 135
8.3 Power Removal......Page 138
8.4 Thermal Stress......Page 139
9.1 Impurity Radiation......Page 141
9.2 Erosion Phenomena in Fusion Experiments......Page 147
9.3 Impurity Transport......Page 160
9.4 Critical Impurity Concentration......Page 182
Part III: Operation Limits and Criteria......Page 185
10 The Problem of Plasma Density Control......Page 186
10.1 Long-Term Operation......Page 188
10.2 Wall Conditioning......Page 190
11 Plasma Operation Limits......Page 193
12 Material Operation Limits......Page 199
12.2 Impurity Density in the Plasma Core......Page 201
12.4 Lifetime of Wall Elements......Page 203
12.5 Neutron Irradiation......Page 213
13 Choice of Materials......Page 216
13.1 Candidates of Materials......Page 219
13.2 Alternative Concepts and Innovative Ideas......Page 223
13.3 Open Questions......Page 224
14 Summary and Outlook......Page 227
A.1 Some Important Relations and Parameters......Page 233
A.2 Simple Particle Mover......Page 239
A.3 Symbols......Page 240
A.4 Abbreviations......Page 246
A.5 Fundamental Physical Constants......Page 249
A.6 Physical Properties of Elements......Page 250
References......Page 254
C......Page 273
H......Page 274
M......Page 275
S......Page 276
Z......Page 277
