Download or read book Numerical Simulation of Ion Thruster and Stationary Plasma Thruster Exhaust Beam Electrostatic Potential Fields written by Michael Sanghun Rhee and published by . This book was released on 1995 with total page 288 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Simulation of Ion Thruster Optics written by and published by . This book was released on 2003 with total page 18 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 Numerical Simulations of the Plumes of Electric Propulsion Thrusters written by Douglas Bryan VanGilder and published by . This book was released on 2000 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book 31st AIAA ASME SAE ASEE Joint Propulsion Conference and Exhibit written by and published by . This book was released on 1995 with total page 538 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Experimental Investigations of Plasma Parameters and Species dependent Ion Energy Distribution in the Plasma Exhaust Plume of a Hall Thruster written by Sang-Wook Kim and published by . This book was released on 1999 with total page 478 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Simulation of Pulsed Plasma Thruster written by Jianjun Wu and published by Springer. This book was released on 2024-11-20 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book are valuable in gaining an understanding of the working mechanism of pulsed plasma thrusters. It facilitates the evaluation of the thruster's working characteristics and propulsive performance, thereby providing a crucial theoretical foundation and reference for the design, development, and engineering application of pulsed plasma thrusters. Additionally, this book significantly contributes to the advancement of space electric propulsion technology. Researchers and engineers in the aerospace propulsion field can greatly benefit from the insights presented within this book. This is an open access book.
Download or read book Development of the Plasma Thruster Particle in cell Simulator to Complement Empirical Studies of a Low power Cusped field Thruster written by Stephen Robert Gildea and published by . This book was released on 2013 with total page 285 pages. Available in PDF, EPUB and Kindle. Book excerpt: Cusped-field plasma thrusters are an electric propulsion concept being investigated by several laboratories in the United States and Europe. This technology was implemented as a low-power prototype in 2007 to ascertain if durability and performance improvements over comparable Hall thruster designs could be provided by the distinct magnetic topologies inherent to these devices. The first device tested at low-powers was eventually designated the "diverging cusped- field thruster" (DCFT) and demonstrated performance capabilities similar to state-of-the-art Hall thrusters. The research presented herein is a continuation of these initial studies, geared toward identifying significant operational characteristics of the thruster using experiments and numerical simulations. After a review of hybrid, fluid, and particle-in-cell Hall thruster models, experimental contributions from this work are presented. Anode current waveform measurements provide the first evidence of the distinct time-dependent characteristics of the two main modes of DCFT operation. The previously named "high-current" mode exhibits oscillation amplitudes several factors larger than mean current values, while magnitudes in "low-current" mode are at least a full order smaller. Results from a long-duration test, exceeding 200 hours of high-current mode operation, demonstrate lifetime-limiting erosion rates about 50% lower than those observed in comparable Hall thrusters. Concurrently, the plasma thruster particle-in-cell (PTpic) simulator was developed by upgrading numerous aspects of a preexisting Hall thruster model. Improvements in performance and accuracy have been achieved through modifications of the particle moving and electrostatic potential solving algorithms. Data from simulations representing both modes of operation are presented. In both cases, despite being unable to predict the correct location of the main potential drop in the thruster chamber, the model successfully reproduces the hollow conical jet of fast ions in the near plume region. The influences guiding the formation of the simulated beam in low-current mode are described in detail. A module for predicting erosion rates on dielectric surfaces has also been incorporated into PTpic and applied to simulations of both DCFT operational modes. Two data sets from highcurrent mode simulations successfully reproduce elevated erosion profiles in each of the three magnetic ring-cusps present in the DCFT. Discrepancies between the simulated and experimental data do exist, however, and are once again attributable to the misplacement of the primary acceleration region of the thruster. Having successfully captured the most significant erosion profile features observed in high-current mode, a simulation of erosion in low-current mode indicates substantially reduced erosion in comparison to the more oscillatory mode. These findings further motivate the completion of low-current mode erosion measurements, and continued numerical studies of the DCFT. Additionally, PTpic has proven to be a useful simulation tool for this project, and has been developed with adaptability in mind to facilitate its application to a variety of thruster designs -- including Hall thrusters.
Download or read book International Aerospace Abstracts written by and published by . This book was released on 1999 with total page 1032 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Dissertation Abstracts International written by and published by . This book was released on 1996 with total page 860 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Numerical Simulations of Ion Thruster Induced Plasma Dynamics written by Carsten Othmer and published by . This book was released on 2001 with total page 346 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Field Structure and Electron Transport in the Near field of Coaxial Hall Thrusters written by Andrew Wayne Smith and published by . This book was released on 2010 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The Hall thruster is an electric propulsion device developed in the former USSR during the Cold War, capable of efficiently providing sustained, low-levels of thrust. Coaxial Hall thrusters are comprised of an annular channel (at the base of which the anode is generally found), and a series of electromagnets that produce a predominantly radial magnetic field near the channel exit. A cathode, located outside the annular channel, injects electrons that serve a dual purpose: they neutralize the ion beam, and they sustain the core discharge. They plasma ions can achieve considerable exhaust velocities, lending the Hall thruster a high specific impulse; however, the propellant flow rate is generally on the order of a few mg/s, keeping the overall thrust low. Despite their desirable high efficiency, the detailed physics of Hall thruster operation is not clearly understood. In particular, the mechanism by which electrons are able to diffuse across the magnetic field lines at a rate in excess of classical predictions is the subject of dispute and ongoing research. Rectifying this deficiency within the near-field region (defined to lie between the exit plane of the annular channel and the external cathode) is the primary motivation for this work. A clear understanding of the mechanisms of electron transport in the near-field can aid the development of more efficient thrusters and provide direction for future experiments. The present study approaches the problem on two fronts. First, an extensive, 3-D map of the plasma potential (in addition to the floating potential and electron temperature) is obtained via a series of time-resolved experiments. These transient measurements are referenced to the periodic oscillation in the discharge current of Hall thrusters (known as the breathing-mode) and provide an unprecedented visualization of the low-frequency field dynamics. Second, the electron transport physics in the near-field is investigated in 3-D, electron-kinetic simulations. These simulations implement the experimentally-observed plasma potential (and, in some cases, fluctuations in the plasma potential). These simulations demonstrate that the 3-D nature of the fields is an important driver of near-field transport; however, collisions with the front-face of the thruster are critical to the anomalous diffusion of electrons across the magnetic field lines in this region. In simulations that considered static fields, up to 35 % of the electrons reached the channel during simulated lifetimes exceeding 1 microsecond, but often yielded very inhomogeneous density distributions. Imposing the measured helical plasma potential fluctuations in the simulations resulted in a dramatic azimuthal homogenization of the electron density distribution, and reduced the fraction of electrons reaching the channel to about 10 %, on par with experimental observations. In every case tested, plasma potential fluctuations (both axial and helical at a variety of frequencies) reduced the electron current reaching the channel. The results further suggest that the location and orientation of the cathode (as well as the properties of the emitted electron beam) have a strong effect on the transport. Gas-phase collisions, even when allowed to occur at a greatly exaggerated rate, are found to have negligible effect on either the channel/beam current ratio or the density distribution in the near-field. These results also suggest that random turbulence in the plasma properties (at least for frequencies less than or equal to 10 MHz) is unlikely to significantly impact the net electron transport (i.e., the channel/beam current ratio or density distribution). Importantly, axisymmetric simulations are found to yield dramatically disparate results (often yielding zero electron-current transport to the channel) compared to the simulations that considered 3-D fields (which introduce azimuthal components in the electric and magnetic fields); a result which questions the validity of pervasive 2-D Hall thruster simulations.
Download or read book A Theoretical and Numerical Study of the Use of Grid Embedded Axial Magnetic Fields to Reduce Charge Exchange Ion Induced Grid Erosion in Electrostatic Ion Thrusters written by Ian R. Claypool and published by . This book was released on 2007 with total page 257 pages. Available in PDF, EPUB and Kindle. Book excerpt: Decay of ion thruster grids due to impact by charge exchange ions is the main life limiting factor in ion propulsion systems. Any system which can reduce the number or energy of ions impacting the grids will add to the life expectancy at current power levels. One possible technique for reducing damage from charge exchange ions would involve the incorporation in the grids of axial aligned embedded "micro-solenoid" magnetic fields. These fields, generated by currents running around the grid apertures would form mini magnetic nozzles guiding beam ions through the aperture while diverting charge exchange ions from directly impacting the grids. Evaluation of different grid geometries, grid fields, or the use of external or internal auxiliary fields as means to limit charge exchange induced grid erosion is difficult to accomplish either experimentally or computationally. For the sole purpose of quickly testing and evaluating different arrangements of grid geometry and fields a simpler computational model which only evaluates the motion of charge exchange ions would be useful in arriving at a reduced set of potential improved configurations that can then be evaluated by more sophisticated computational and eventually experimental means. A simple computational simulation of the environment within a single set of ion thruster grids has been created for use in evaluating the response of single charge exchange ions to many different grid geometries and field arrangements. This effort involved the development of the ionLite code which simulates the grid geometries, fields, and ion beam charge distribution while allowing individual charge exchange ions to be created at any point and their trajectories and eventual fates to be determined. Using this code the use of auxiliary magnetic fields was examined. This analysis shows that energy transfer to a simulated accelerator grid from charge exchange ions can be reduced by approximately 20%, but only at vary large magnitude magnetic field strengths (order of 100 T). It was found that for the configurations investigated the optimum performance resulted when the applied magnetic field was just enough to cause the particle Larmor radius to be approximately equal to the grid aperture radius. The use of lower mass propellants such as neon or helium allow for this benefit at fields on the order of 20 T. The potential impact of the embedded magnetic fields is shown to be very sensitive to grid geometry, and therefore it is probable that a different configuration could provide even greater reduction in kinetic energy transfer at moderate field levels.
Download or read book Physics of Electric Propulsion written by Robert G. Jahn and published by Courier Corporation. This book was released on 2006-05-26 with total page 370 pages. Available in PDF, EPUB and Kindle. Book excerpt: Literaturangaben. - Originally published: New York, NY : McGraw-Hill, 1968
Download or read book American Doctoral Dissertations written by and published by . This book was released on 1995 with total page 896 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Performance Evaluation of the SPT 140 written by and published by . This book was released on 1997 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Selected Topics in Plasma Physics written by Sukhmander Singh and published by BoD – Books on Demand. This book was released on 2020-11-19 with total page 146 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book is planned to introduce the advances topics of plasma physics for research scholars and postgraduate students. This book deals with basic concepts in plasma physics, non-equilibrium plasma modeling, space plasma applications, and plasma diagnostics. It also provides an overview of the linear and nonlinear aspects of plasma physics. Chapters cover such topics as plasma application in space propulsion, microwave–plasma interaction, plasma antennas, solitary waves, and plasma diagnostic techniques.
