Electrothermics

This book concerns the analysis and design of induction heating of poor electrical conduction materials. Some innovating applications such as inductive plasma installation or transformers, thermo inductive non-destructive testing and carbon-reinforced composite materials heating are studied. Analytical, semi-analytical and numerical models are combined to obtain the best modeling technique for each case. Each model has been tested with experimental results and validated. The principal aspects of a computational package to solve these kinds of coupled problems are described. In the first chapter, the mathematical tools for coupled electromagnetic and thermal phenomena are introduced. In Chapter 2, these tools are used to analyze a radio frequency inductive plasma installation. The third chapter describes the methodology of designing a low frequency plasma transformer. Chapter 4 studies the feasibility of the thermo inductive technique for non-destructive testing and the final chapter is dedicated to the use of induction heating in the lifecycle of carbon-reinforced composite materials.

Introduction xiii Javad FOULADGAR Chapter 1. Thermal and Electromagnetic Coupling 1 Javad FOULADGAR, Didier TRICHET and Brahim RAMDANE 1.1. Introduction 1 1.2. Electromagnetic problem 2 1.3. Thermal problem 15 1.4. Magnetothermal coupling 16 1.5. Solving the electromagnetic and thermal equations 18 1.6. Conclusion 35 1.7. Bibliography 36 Chapter 2. Simplified Model of a Radiofrequency Inductive Thermal Plasma Installation 39 Javad FOULADGAR and Jean-Pierre PLOTEAU 2.1. Introduction 39 2.2. Plasma and its characteristics 40 2.3. Modeling a plasma installation 49 2.4. Calculating charge impedance 57 2.5. Generator model 64 2.6. Conclusion 80 2.7. Bibliography 81 Chapter 3. Design Methodology of A Very Low-Frequency Plasma Transformer 85 Javad FOULADGAR and Souri Mohamed MIMOUNE 3.1. Introduction 85 3.2. Different types of very low-frequency applicators 87 3.3. Simplified analytical model for analysis and preliminary design 88 3.4. Nonlinear model 97 3.5. Plasma stability in the transitory and sinusoidal states 100 3.6. Advanced inductive plasma transformer model 103 3.7. Plasma initialization 111 3.8. Conclusion 114 3.9. Bibliography 114 Chapter 4. Non Destructive Testing by Thermo-Inductive Method 117 Javad FOULADGAR, Brahim RAMDANE, Didier TRICHET and Tayeb SAIDI 4.1. Introduction 117 4.2. Principles of the thermo-inductive method 119 4.3. Basic thermo-inductive technique theory 126 4.4. Application of the thermo-inductive method to inspect massive magnetic steel  components 145 4.5. Comparison with infrared thermography 164 4.6. Applications on composite materials 168 4.7. Conclusion and general instructions 185 4.8. Bibliography 190 Chapter 5. Induction Heating of Composite Materials 195 Javad FOULADGAR, Didier TRICHET, Samir BENSAID and Guillaume WASSELYNCK 5.1. Introduction 195 5.2. Composite materials 197 5.3. Lifecycle of composite materials 202 5.4. Induction and the lifecycle of composite materials 203 5.5. Identifying the physical properties of composite materials by experimental methods 207 5.6. Homogenization techniques 224 5.7. Heating composite materials by induction 251 5.8. Setup model 253 5.9. Influence of the folds’ orientation 260 5.10. Difficulty of the electrothermal coupling 262 5.11. Validating the electrothermal model 262 5.12. Conclusion 267 5.13. Bibliography 268 List of Authors 273 Index 275