Preface

**Section 2 Modern Applications of Plasma 145**

**VI** Contents

Chapter 9 **Plasma-Assisted Combustion 167**

**Plasma Thruster 189**

Xiaobin Zhu

Yasunori Ohtsu

**Airflows 247**

Chapter 8 **A Test Facility to Investigate Sheath Effects during Ion**

Kristel Crombe, Rodolphe D' Inca, Eric Faudot, Helmut Faugel, Ana Kostic, Mariia Usoltceva, Jean-Marie Noterdaeme, Anton Nikiforov, Helmut Fuenfgelder, Stephane Heuraux, Jonathan Jacquot, Fabrice Louche, Roman Ochoukov, Ilya Shesterikov and Dirk Van Eester

Siyin Zhou, Haiqing Wang, Wansheng Nie and Xueke Che

Jianjun Wu, Yu Zhang, Yuqiang Cheng, Qiang Huang, Jian Li and

**Plasma with Various Electrodes and Its Applications 209**

Daniel P. Engelhart, Elena A. Plis, Dale Ferguson, W. Robert

Chapter 10 **Plasma Generation and Application in a Laser Ablation Pulsed**

Chapter 11 **Physics of High-Density Radio Frequency Capacitively Coupled**

Chapter 12 **Space Plasma Interactions with Spacecraft Materials 225**

Johnston, Russell Cooper and Ryan C. Hoffmann

Chapter 13 **Repetitive Nanosecond Volume Discharges under**

Jingfeng Tang, Liqiu Wei and Daren Yu

Chapter 14 **Modeling of Novel Plasma-Optical Systems 267** Iryna Litovko and Alexey Goncharov

Chapter 15 **Plasma Damage on Low-k Dielectric Materials 291**

Yi-Lung Cheng, Chih-Yen Lee and Chiao-Wei Haung

**Cyclotron Resonance Heating 147**

Most of the matter in the universe is in a state called plasma. It exhibits complex and rich phenomena. Studying plasmas is essential for technology development and applications in tokamak reactors, medicine, and the environment. Plasma physics studies also allow an un‐ derstanding of processes in the interstellar medium and in solar physics.

The aim of this book is to provide a basic knowledge of plasma science and technology to the common reader. The book will be useful for researchers and students. It provides a large overview from basic fundamentals to modern applications related to plasma science and technology. This was reached by presenting new experimental and theoretical results, and interdisciplinary and outstanding applications in plasma physics.

The editors hope that *Plasma Science & Technology: Basic Fundamentals and Modern Applica‐ tions* will be useful to a large audience among researchers and students.

**Prof. Dr. Haikel Jelassi**

Laboratory "Energy and Matter for Nuclear Sciences Development" (LR16CNSTN02) National Centre for Nuclear Sciences and Technologies Sidi Thabet Technopark Ariana, Tunisia

**Prof. Djamel Benredjem**

Laboratoire Aimé Cotton, CNRS and University Paris-Saclay Orsay, France

**Section 1**

**Fundamentals of Plasma Physics**

**Fundamentals of Plasma Physics**

**Chapter 1**

Provisional chapter

**Noise-Free Rapid Approach to Solve Kinetic Equations**

DOI: 10.5772/intechopen.76681

At the first wall of a fusion reactor, charged plasma particles are recombined into neutral molecules and atoms recycling back into the plasma volume where charge exchange (cx) with ions. As a result hot atoms with chaotically directed velocities are generated which can strike and erode the wall. An approach to solve the kinetic equation in integral form for cx atoms, being alternative to statistical Monte Carlo methods, has been speeded up by a factor of 50, by applying an approximate pass method to evaluate integrals, involving the ion velocity distribution function. It is applied to two-dimensional transfer of cx atoms near the entrance of a duct, guiding to the first mirror for optical observations. The energy spectrum of hot cx atoms, escaping into the duct, is calculated and the mirror erosion rate is assessed. Computations are done for a molybdenum first mirror under plasma conditions expected in the fusion reactor DEMO. Kinetic modeling results are compared with those found with a diffusion approximation valid in very cold and dense plasmas. For ducts at the torus outboard a more rigorous kinetic consideration predicts an erosion rate

Noise-Free Rapid Approach to Solve Kinetic Equations

**for Hot Atoms in Fusion Plasmas**

for Hot Atoms in Fusion Plasmas

Additional information is available at the end of the chapter

by a factor up to 2 larger than the diffusion approximation.

Keywords: fusion, plasma, neutral, atoms, kinetic equation, numerical solution

In devices for thermonuclear fusion research, for example, of the Tokamak type, particles of hydrogen isotopes, deuterium and tritium, are in the form of a hot fully ionized plasma [1, 2]. To avoid a destruction of the machine wall, a special region, the so-called scrape-off layer (SOL), is arranged at the plasma edge, where particles stream along the magnetic field to the

> © 2016 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and eproduction in any medium, provided the original work is properly cited.

© 2018 The Author(s). Licensee IntechOpen. This chapter is distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use,

distribution, and reproduction in any medium, provided the original work is properly cited.

Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.76681

Mikhail Tokar

Mikhail Tokar

Abstract

1. Introduction

#### **Noise-Free Rapid Approach to Solve Kinetic Equations for Hot Atoms in Fusion Plasmas** Noise-Free Rapid Approach to Solve Kinetic Equations for Hot Atoms in Fusion Plasmas

DOI: 10.5772/intechopen.76681

#### Mikhail Tokar Mikhail Tokar

Additional information is available at the end of the chapter Additional information is available at the end of the chapter

http://dx.doi.org/10.5772/intechopen.76681

#### Abstract

At the first wall of a fusion reactor, charged plasma particles are recombined into neutral molecules and atoms recycling back into the plasma volume where charge exchange (cx) with ions. As a result hot atoms with chaotically directed velocities are generated which can strike and erode the wall. An approach to solve the kinetic equation in integral form for cx atoms, being alternative to statistical Monte Carlo methods, has been speeded up by a factor of 50, by applying an approximate pass method to evaluate integrals, involving the ion velocity distribution function. It is applied to two-dimensional transfer of cx atoms near the entrance of a duct, guiding to the first mirror for optical observations. The energy spectrum of hot cx atoms, escaping into the duct, is calculated and the mirror erosion rate is assessed. Computations are done for a molybdenum first mirror under plasma conditions expected in the fusion reactor DEMO. Kinetic modeling results are compared with those found with a diffusion approximation valid in very cold and dense plasmas. For ducts at the torus outboard a more rigorous kinetic consideration predicts an erosion rate by a factor up to 2 larger than the diffusion approximation.

Keywords: fusion, plasma, neutral, atoms, kinetic equation, numerical solution
