Download or read book Model of Plasma wall Interaction Effects in a Hall Thruster written by E. Ahedo and published by . This book was released on 2001 with total page 11 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Modeling the Effect of Plasma wall Interaction in a Hall Thruster written by Subrata Roy and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Model of Radial Plasma wall Interactions in a Hall Thruster Discharge written by E. Ahedo and published by . This book was released on 2002 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Fundamentals of Electric Propulsion written by Dan M. Goebel and published by John Wiley & Sons. This book was released on 2008-12-22 with total page 528 pages. Available in PDF, EPUB and Kindle. Book excerpt: Throughout most of the twentieth century, electric propulsion was considered the technology of the future. Now, the future has arrived. This important new book explains the fundamentals of electric propulsion for spacecraft and describes in detail the physics and characteristics of the two major electric thrusters in use today, ion and Hall thrusters. The authors provide an introduction to plasma physics in order to allow readers to understand the models and derivations used in determining electric thruster performance. They then go on to present detailed explanations of: Thruster principles Ion thruster plasma generators and accelerator grids Hollow cathodes Hall thrusters Ion and Hall thruster plumes Flight ion and Hall thrusters Based largely on research and development performed at the Jet Propulsion Laboratory (JPL) and complemented with scores of tables, figures, homework problems, and references, Fundamentals of Electric Propulsion: Ion and Hall Thrusters is an indispensable textbook for advanced undergraduate and graduate students who are preparing to enter the aerospace industry. It also serves as an equally valuable resource for professional engineers already at work in the field.

Download or read book Electron Wall Interaction in Hall Thrusters written by Y. Raitses and published by . This book was released on 2005 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book One Dimensional Analysis of Hall Thruster Operating Modes written by and published by . This book was released on 2001 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The very simplicity of the Hall thruster structure with no screens or other control surfaces makes it difficult to understand the interrelationships which, in the end, localize and shape the various plasma regions existing in the accelerating channel. Since the radial magnetic field is usually shaped with a peak near the channel exit, the plasma structure has often been explained as simply a reflection of the magnetic field distribution. However, this is inadequate to explain the plasma dynamics inside the accelerating channel. We develop a macroscopic model gathering reliability and clarity. Quantitative accuracy in the predictions is not the main goal. Instead, emphasis is given to the consistency of the governing equations and their boundary conditions, and to include enough basic physics to illuminate the complex interplay of phenomena which shape the Hall thruster plasma. A basic model is presented along with a supplementary model of the radial interaction of the plasma with the lateral walls of the thruster. An analysis is presented of the effects of the radial plasma/wall interactions on the basic steady-state solution. The effects of heat conduction and plasma oscillations are discussed.

Download or read book Electron Wall Interaction in Hall Thrusters written by Y. Raitses and published by . This book was released on 2005 with total page 46 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plasma Engineering written by Michael Keidar and published by Academic Press. This book was released on 2018-08-06 with total page 586 pages. Available in PDF, EPUB and Kindle. Book excerpt: Plasma Engineering, Second Edition, applies the unique properties of plasmas (ionized gases) to improve processes and performance over many fields, such as materials processing, spacecraft propulsion and nanofabrication. The book considers this rapidly expanding discipline from a unified standpoint, addressing fundamentals of physics and modeling, as well as new and real-word applications in aerospace, nanotechnology and bioengineering. This updated edition covers the fundamentals of plasma physics at a level suitable for students using application examples and contains the widest variety of applications of any text on the market, spanning the areas of aerospace engineering, nanotechnology and nanobioengineering. This is highly useful for courses on plasma engineering or plasma physics in departments of Aerospace Engineering, Electrical Engineering and Physics. It is also useful as an introduction to plasma engineering and its applications for early career researchers and practicing engineers. Features new material relevant to application, including emerging areas of plasma nanotechnology and medicine Contains a new chapter on plasma-based control, as well as a description of RF and microwave-based plasma applications, plasma lighting, reforming and other most recent application areas Provides a technical treatment of the fundamental and engineering principles used in plasma applications

Download or read book Fundamentals of Electric Propulsion written by Dan M. Goebel and published by John Wiley & Sons. This book was released on 2023-10-25 with total page 564 pages. Available in PDF, EPUB and Kindle. Book excerpt: Fundamentals of Electric Propulsion Understand the fundamental basis of spaceflight with this cutting-edge guide As spacecraft engineering continues to advance, so too do the propulsion methods by which human beings can seek out the stars. Ion thrusters and Hall thrusters have been the subject of considerable innovation in recent years, and spacecraft propulsion has never been more efficient. For professionals within and adjacent to spacecraft engineering, this is critical knowledge that can alter the future of space flight. Fundamentals of Electric Propulsion offers a thorough grounding in electric propulsion for spacecraft, particularly the features and mechanisms underlying Ion and Hall thrusters. Updated in the light of rapidly expanding knowledge, the second edition of this essential guide detailed coverage of thruster principles, plasma physics, and more. It reflects the historic output of the legendary Jet Propulsion Laboratory and promises to continue as a must-own volume for spacecraft engineering professionals. Readers of the second edition of Fundamentals of Electric Propulsion readers will also find: Extensive updates to chapters covering hollow cathodes and Hall thrusters, based on vigorous recent research New sections covering magnetic shielding, cathode plume instabilities, and more Figures and homework problems in each chapter to facilitate learning and retention Fundamentals of Electric Propulsion is an essential work for spacecraft engineers and researchers working in spacecraft propulsion and related fields, as well as graduate students in electric propulsion, aerospace science, and space science courses.

Download or read book 37th AIAA ASME SAE ASEE Joint Propulsion Conference Exhibit written by and published by . This book was released on 2001 with total page 450 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Development of a Computationally Efficient High Fidelity Finite Element Based Hall Thruster Model written by National Aeronautics and Space Administration (NASA) and published by Createspace Independent Publishing Platform. This book was released on 2018-06-21 with total page 26 pages. Available in PDF, EPUB and Kindle. Book excerpt: This report documents the development of a two dimensional finite element based numerical model for efficient characterization of the Hall thruster plasma dynamics in the framework of multi-fluid model. Effect of the ionization and the recombination has been included in the present model. Based on the experimental data, a third order polynomial in electron temperature is used to calculate the ionization rate. The neutral dynamics is included only through the neutral continuity equation in the presence of a uniform neutral flow. The electrons are modeled as magnetized and hot, whereas ions are assumed magnetized and cold. The dynamics of Hall thruster is also investigated in the presence of plasma-wall interaction. The plasma-wall interaction is a function of wall potential, which in turn is determined by the secondary electron emission and sputtering yield. The effect of secondary electron emission and sputter yield has been considered simultaneously, Simulation results are interpreted in the light of experimental observations and available numerical solutions in the literature. Jacobson, David (Technical Monitor) and Roy, Subrata Glenn Research Center

Download or read book Low Power Magnetically Shielded Hall Thrusters written by Ryan Conversano and published by . This book was released on 2015 with total page 240 pages. Available in PDF, EPUB and Kindle. Book excerpt: This dissertation presents an investigation of the applicability of magnetic shielding to low-power Hall thrusters as a means to significantly improve operational lifetime. The key life-limiting factors of conventional Hall thrusters, including ion-bombardment sputter erosion of the discharge channel and high-energy electron power deposition to the channel walls, have been investigated extensively for a wide range of thruster scales. As thruster power is reduced to the "miniature" (i.e. sub-500 W) power regime, the increased surface-to-volume ratio of the discharge channel and decreased thruster component sizes promotes increased plasma-wall interactions and susceptibility to overheating, thereby reducing thruster operational lifetime and performance. Although methods for compensating for these issues have been investigated, unshielded miniature Hall thrusters are generally limited to sub-45% anode efficiencies and maximum lifetimes on the order of 1,000 h. A magnetically shielded magnetic field topology aims to maintain a low electron temperature along the channel surfaces and a plasma potential near that of the discharge voltage along the entire surface of the discharge channel along its axial length. These features result in a reduction of the kinetic energy of ions that impact the channel surfaces to near to or below the sputtering threshold, thus preventing significant ion-bombardment erosion of the discharge channel. Improved confinement of high-energy electrons is another byproduct of the field structure, aiding in the reduction of electron power deposition to the channel. Magnetic shielding has been shown to dramatically reduce plasma-wall interactions on 4 - 6 kW Hall thrusters, resulting in significant increases in projected operational lifetimes with minimal effects to thruster performance. In an effort to explore the scalability of magnetic shielding to low-power devices, two magnetically shielded miniature Hall thrusters were designed, fabricated and tested. The performance of the first thruster, called the MaSMi 40, was characterized at an operating condition of 275 V and 325 W. A peak thrust of approximately 13 mN with a specific impulse of approximately 1,100 s at an anode efficiency of approximately 22% were measured at the nominal operating point. Observations of the near exit plasma discharge during operation, and the discharge channel after operation, suggested that the outer channel wall of the thruster was well shielded from ion bombardment while the inner channel wall appeared to be weakly shielded. Further analysis concluded that the MaSMi-40 generated a partially-magnetically shielded field topology. However, the shortcomings of the MaSMi-40's magnetic circuit design were investigated in detail and are now well understood. The second design iteration in the development of a low-power magnetically shielded Hall thruster was the MaSMi-60. Magnetic field measurements confirmed that a symmetric and fully shielded magnetic field topology was generated by this device across a wide range of possible operating conditions. At operating powers of 160 W to nearly 750 W, the key performance metrics of the MaSMi-60 included a measured thrust ranging from approximately 8 mN to over 33 mN with anode specific impulses of up to approximately 1370 s at anode efficiencies of over 28%. Downstream plume measurements identified the primary factors contributing to the low anode efficiency. Visual observations of the discharge plasma and channel walls during and after thruster operation offered strong evidence of magnetic shielding. Erosion rates of the channel were approximated using carbon backsputter measurements; the results suggested a 10x - 100x decrease in wall erosion compared to unshielded Hall thrusters, corresponding to an equal increase in discharge channel lifetime compared to conventional miniature unshielded Hall thrusters. The physics and behaviors of the MaSMi-60's plasma discharge upstream of and in the near-field of the thruster exit plane were investigated using Hall2De, the 2-D axisymmetric code developed at the Jet Propulsion Laboratory for the simulation of the partially ionized plasma in Hall thrusters. Simulations of the MaSMi-60 suggested that the thruster achieved the plasma properties required for effective magnetic shielding, including low electron temperatures and a near-constant plasma potential along the channel walls. This was the final piece of evidence suggesting that magnetic shielding was attained at the miniature scale. The experimentally measured performance of the MaSMi-60 was captured by the Hall2De model, offering physical explanations for the low measured anode efficiency and leading to suggestions for improving the performance in future design iterations.

Download or read book A Hall Thruster Performance Model Incorporating the Effects of a Multiply Charged Plasma written by Richard R. Hofer and published by . This book was released on 2002 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book 38th AIAA ASME SAE ASEE Joint Propulsion Conference Exhibit 02 4100 02 4149 written by and published by . This book was released on 2002 with total page 624 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Breathing Mode Effects on Hall Thruster Plasma Quantities and Channel Wall Power Loss written by Nadiah Jenkins and published by . This book was released on 2019 with total page 73 pages. Available in PDF, EPUB and Kindle. Book excerpt: Breathing mode instabilities, axially-oriented waves between 5-40 kHz, have been observed in Hall thruster operation since the earliest days of experimental research, including their ability to grow large enough to extinguish the working plasma. Recent forays into higher power Hall thrusters and extended mission durations highlight the need to understand the mechanisms and consequences of the breathing mode. While experiments in the last 20 years have increased the understanding of the time dependent behavior of plasma within the channel, analytical and numerical models have struggled to accurately replicate the oscillation or predict its effects. This thesis presents a partial-D fluid model to numerically solve for plasma and neutral density, ion and electron velocity, and mass utilization in a radially- and azimuthally-symmetric SPT-type Hall thruster. After an ideal steady state solution converges, these quantities evolve in the presence of a driven sinusoidal oscillation of the electric field, which simulates a breathing mode oscillation. Separate simulations vary the frequency and amplitude of the driven oscillations to test spatial and temporal variations of the acceleration region. Then, analysis focuses on how the oscillations affect plasma quantities and key contributors to channel wall power loss. This work provides clarification on how the breathing mode perturbs the plasma and how this compares with experiments in the literature.

Download or read book Flows and Chemical Reactions in an Electromagnetic Field written by Roger Prud'homme and published by John Wiley & Sons. This book was released on 2014-10-30 with total page 134 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book - a sequel of previous publications Flows and Chemical Reactions, Chemical Reactions Flows in Homogeneous Mixtures and Chemical Reactions and Flows in Heterogeneous Mixtures - is devoted to flows with chemical reactions in the electromagnetic field. The first part, entitled basic equations, consists of four chapters. The first chapter provides an overview of the equations of electromagnetism in Minkowski spacetime. This presentation is extended to balance equations, first in homogeneous media unpolarized in the second chapter and homogeneous fluid medium polarized in the third chapter. Chapter four is devoted to heterogeneous media in the presence of electromagnetic field. Balance equations at interfaces therein. The second part of this volume is entitled applications. It also includes four chapters. Chapter five provides a study of the action of fields on fire. Chapter six deals with a typical application for the Peltier effect, chapter seven is devoted to metal-plasma interaction, especially in the Langmuir probe and finally Chapter Eight deals with the propulsion Hall effect. Are given in appendix supplements the laws of balance with electromagnetic field and described the methodology for establishing one-dimensional equations for flow comprising active walls as is the case in some Hall effect thrusters.

Download or read book Plasma Simulations by Example written by Lubos Brieda and published by CRC Press. This book was released on 2019-12-13 with total page 348 pages. Available in PDF, EPUB and Kindle. Book excerpt: The study of plasmas is crucial in improving our understanding of the universe, and they are being increasingly utilised in key technologies such as spacecraft thrusters, plasma medicine, and fusion energy. Providing readers with an easy to follow set of examples that clearly illustrate how simulation codes are written, this book guides readers through how to develop C++ computer codes for simulating plasmas primarily with the kinetic Particle in Cell (PIC) method. This text will be invaluable to advanced undergraduates and graduate students in physics and engineering looking to learn how to put the theory to the test. Features: Provides a step-by-step introduction to plasma simulations with easy to follow examples Discusses the electrostatic and electromagnetic Particle in Cell (PIC) method on structured and unstructured meshes, magnetohydrodynamics (MHD), and Vlasov solvers Covered topics include Direct Simulation Monte Carlo (DSMC) collisions, surface interactions, axisymmetry, and parallelization strategies. Lubos Brieda has over 15 years of experience developing plasma and gas simulation codes for electric propulsion, contamination transport, and plasma-surface interactions. As part of his master’s research work, he developed a 3D ES-PIC electric propulsion plume code, Draco, which is to this date utilized by government labs and private aerospace firms to study plasma thruster plumes. His Ph.D, obtained in 2012 from George Washington University, USA, focused on a multi-scale model for Hall thrusters utilizing fluid-kinetic hybrid PIC codes. He has since then been involved in numerous projects involving development and the use of plasma simulation tools. Since 2014 he has been teaching online courses on plasma simulations through his website: particleincell.com.