|
Title Page |
4 |
|
|
Copyright Page |
5 |
|
|
Preface |
6 |
|
|
Table of Contents |
12 |
|
|
1 Setting the problem |
15 |
|
|
1.1 Maxwell equations and time-harmonic Maxwell equations |
15 |
|
|
1.2 Eddy currents and eddy current approximation |
18 |
|
|
1.3 Geometrical setting and boundary conditions |
22 |
|
|
1.4 Harmonic fields in electromagnetism |
24 |
|
|
1.5 The complete eddy current model |
29 |
|
|
2 A mathematical justification of the eddy current model |
34 |
|
|
2.1 The E-based formulation of Maxwell equations |
34 |
|
|
2.2 The eddy current model as the low electric permittivity limit |
38 |
|
|
2.3 The eddy current model as the low-frequency limit |
40 |
|
|
2.3.1 Higher order convergence |
43 |
|
|
3 Existence and uniqueness of the solution |
48 |
|
|
3.1 Weak formulation, existence and uniqueness for the magnetic field |
49 |
|
|
3.2 Determination of the electric field |
51 |
|
|
3.3 Strong formulation for the magnetic field |
56 |
|
|
3.3.1 The Faraday equation for the “cutting” surfaces |
59 |
|
|
3.3.2 Suitability of other formulations |
61 |
|
|
3.4 Existence and uniqueness for the complete eddy current model |
64 |
|
|
3.5 Other boundary conditions |
65 |
|
|
4 Hybrid formulations for the electric and magnetic fields |
71 |
|
|
4.1 Hybrid formulation using the magnetic field in the insulator |
72 |
|
|
4.2 A saddle-point approach for the EC /HI formulation |
74 |
|
|
4.2.1 Finite element discretization |
79 |
|
|
4.3 A saddle-point approach for the H-based formulation |
88 |
|
|
4.4 Hybrid formulation using the electric field in the insulator |
90 |
|
|
4.5 A saddle-point approach for the HC /EI formulation |
95 |
|
|
4.5.1 Finite element discretization |
99 |
|
|
4.5.2 Some remarks on implementation |
104 |
|
|
4.5.3 Numerical results |
109 |
|
|
4.6 A saddle-point approach for the E-based formulation |
116 |
|
|
5 Formulations via scalar potentials |
123 |
|
|
5.1 The weak formulation in terms of HC and ?I |
124 |
|
|
5.2 The strong formulation in terms of HC and ?I |
129 |
|
|
5.2.1 A domain decomposition procedure |
131 |
|
|
5.3 The formulation in terms of EC and ??I |
132 |
|
|
5.3.1 A domain decomposition procedure |
136 |
|
|
5.4 Numerical approximation |
137 |
|
|
5.4.1 The determination of a vector potential for the density current Je,I |
138 |
|
|
5.4.2 Finite element approximation |
140 |
|
|
5.5 The finite element approximation of EI |
152 |
|
|
6 Formulations via vector potentials |
158 |
|
|
6.1 Formulation for the Coulomb gauge and its numerical approximation |
159 |
|
|
6.1.1 The weak formulation |
165 |
|
|
6.1.2 Existence and uniqueness of the solution to the weak formulation |
172 |
|
|
6.1.3 Numerical approximation |
176 |
|
|
6.1.4 Numerical results |
181 |
|
|
6.1.5 A penalized formulation for the electric field |
188 |
|
|
6.2 Formulation for the Lorenz gauge and its numerical approximation |
191 |
|
|
6.2.1 Decoupled weak formulations and alternative gauge conditions |
194 |
|
|
6.2.2 Well-posed formulations based on the Lorenz gauge |
199 |
|
|
6.2.3 Weak formulations and positiveness |
202 |
|
|
6.2.4 Numerical approximation |
205 |
|
|
6.3 Other potential formulations |
206 |
|
|
7 Coupled FEM–BEM approaches |
216 |
|
|
7.1 The (AC, VC ) ? ?I formulation |
218 |
|
|
7.2 The (AC, VC ) ? ?? weak formulation |
220 |
|
|
7.3 Existence and uniqueness of the weak solution |
224 |
|
|
7.4 Stability as ? goes to 0 |
227 |
|
|
7.5 Numerical approximation |
229 |
|
|
7.5.1 The non-convex case |
232 |
|
|
7.6 Other FEM–BEM approaches |
232 |
|
|
7.6.1 The code TRIFOU |
232 |
|
|
7.6.2 An approach based on the magnetic field HC |
235 |
|
|
7.6.3 An approach based on the electric field EC |
241 |
|
|
8 Voltage and current intensity excitation |
246 |
|
|
8.1 The eddy current problem in the presence of electric ports |
247 |
|
|
8.1.1 Hybrid formulations in term of EC and ??I |
249 |
|
|
8.1.2 Formulations in terms of HC and ??I |
259 |
|
|
8.1.3 Formulations in terms of TC and ??I |
261 |
|
|
8.1.4 Finite element approximation |
265 |
|
|
8.1.5 Numerical results |
269 |
|
|
8.2 Voltage and current intensity excitation for an internal conductor |
274 |
|
|
8.2.1 Variational formulations |
278 |
|
|
9 Selected applications |
286 |
|
|
9.1 Metallurgical thermoelectrical problems |
286 |
|
|
9.1.1 Induction furnaces |
287 |
|
|
9.1.2 Metallurgical electrodes |
290 |
|
|
9.2 Bioelectromagnetism: EEG and MEG |
297 |
|
|
9.3 Magnetic levitation |
304 |
|
|
9.4 Power transformers |
309 |
|
|
9.5 Defect detection |
314 |
|
|
Appendix |
319 |
|
|
A.1 Functional spaces and notation |
319 |
|
|
A.2 Nodal and edge finite elements |
323 |
|
|
A.2.1 Grad-conforming finite elements |
324 |
|
|
A.2.2 Curl-conforming finite elements |
327 |
|
|
A.3 Orthogonal decomposition results |
331 |
|
|
A.3.1 First decomposition result |
331 |
|
|
A.3.2 Second decomposition result |
334 |
|
|
A.3.3 Third decomposition result |
336 |
|
|
A.4 More on harmonic fields |
337 |
|
|
References |
340 |
|
|
Index |
353 |
|