Download or read book Enhanced Performance of Cylindrical Hall Thrusters written by and published by . This book was released on 2007 with total page 368 pages. Available in PDF, EPUB and Kindle. Book excerpt: The cylindrical thruster differs significantly in its underlying physical mechanisms from the conventional annular Hall thruster. It features high ionization efficiency, quiet operation, ion acceleration in a large volume-to-surface ratio channel, and performance comparable with the state-of-the-art conventional Hall thrusters. Very significant plume narrowing, accompanied by the increase of the energetic ion fraction and improvement of ion focusing, led to 50%-60% increase of the thruster anode efficiency. These improvements were achieved by overrunning the discharge current in the magnetized thruster plasma.
Download or read book Optimization of Cylindrical Hall Thrusters written by and published by . This book was released on 2007 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: The cylindrical Hall thruster features high ionization efficiency, quiet operation, and ion acceleration in a large volume-to-surface ratio channel with performance comparable with the state-of-the-art annular Hall thrusters. These characteristics were demonstrated in low and medium power ranges. Optimization of miniaturized cylindrical thrusters led to performance improvements in the 50-200W input power range, including plume narrowing, increased thruster efficiency, reliable discharge initiation, and stable operation. __________________________________________________
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 Enhanced Ionization in the Cylindrical Hall Thruster written by A. I. Smirnov and published by . This book was released on 2003 with total page 33 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electric Field written by Mohsen Sheikholeslami Kandelousi and published by BoD – Books on Demand. This book was released on 2018-05-23 with total page 324 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the present book, various applications of electric field are introduced in health and biology like treating cancer and cell sorting and in engineering and technological applications like enhancing the heat transfer, colloidal hydrodynamics and stability, and lithography. Electric field is defined as a force field arising from the electric charges. Depending on the nature of the material (the ability to polarize) and the inherent or attained surface charges, the response of the electric field varies.
Download or read book Performance Studies of Miniaturized Cylindrical and Annular Hall Thrusters written by A. Smirnov 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 A Study of Cylindrical Hall Thruster for Low Power Space Applications written by Y. Raitses and published by . This book was released on 2000 with total page 13 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Cathode Effects in Cylindrical Hall Thrusters written by and published by . This book was released on 2008 with total page 584 pages. Available in PDF, EPUB and Kindle. Book excerpt: Stable operation of a cylindrical Hall thruster (CHT) has been achieved using a hot wire cathode, which functions as a controllable electron emission source. It is shown that as the electron emission from the cathode increases with wire heating, the discharge current increases, the plasma plume angle reduces, and the ion energy distribution function shifts toward higher energies. The observed effect of cathode electron emission on thruster parameters extends and clarifies performance improvements previously obtained for the overrun discharge current regime of the same type of thruster, but using a hollow cathode-neutralizer. Once thruster discharge current saturates with wire heating, further filament heating does not affect other discharge parameters. The saturated values of thruster discharge parameters can be further enhanced by optimal placement of the cathode wire with respect to the magnetic field.
Download or read book Development of a Miniature Low Power Cylindrical Hall Thruster for Microsatellites written by Carl Pigeon and published by . This book was released on 2017 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: To enable more advanced commercial microsatellite missions, a low power electric propulsion system was designed by the University of Toronto Space Flight Laboratory. A prototype cylindrical Hall thruster was first developed using electromagnets. The thruster's performance was evaluated over a range of 20-300 W. At the nominal 200 W operation, 6.2 mN of thrust with a specific impulse of 1139 s was measured with xenon propellant. Significant erosion of the thruster's discharge chamber wall was observed which limited its lifetime to 100 hours. Subsequently, a flight representative version of the thruster was developed. Permanent magnets were used to reduce the size, mass, and power consumption. Changes to the design were implemented to improve lifetime. Performance characterization and literature suggest that a reduction in performance is expected with the use of permanent magnets. Lastly, thermal vacuum and vibration tests were performed to bring the thruster to Technology Readiness Level 6.
Download or read book Improvements to a Fully Kinetic Hall Thruster Simulation Code and Characterization of the Cylindrical Cusped Field Thruster written by Louis Boulanger (S.M.) and published by . This book was released on 2014 with total page 99 pages. Available in PDF, EPUB and Kindle. Book excerpt: This thesis presents an effort towards a better understanding of the operation of miniaturized cylindrical Hall thrusters. This class of space propulsion devices has come under attention since the 1990s as a possible candidate for the propulsion of 100-1000 kg satellites. In first part, a fully kinetic simulation code developed at the MIT Space Propulsion Laboratory (SPL) is described and applied to two devices of interest: the Princeton Cylindrical Hall Thruster (CHT) and the MIT DCFT (Diverging Cusped-Field Thruster). During this simulation effort, limitations of PTpic were identified which prompted a major redesign, whose central idea is a better parallelization of the workload. At the same time, possible candidates to replace the leapfrog algorithm in the particle pusher have been studied. This work is described in Chapter 3. Finally, chapter 4 presents the results of the testing of the recently built Cylindrical Cusped-Field Thruster (CCFT) performed at the SPL.
Download or read book Parametric Investigation of Miniaturized Cylindrical and Annular Hall Thrusters written by A. I. Smirnov and published by . This book was released on 2002 with total page 29 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Electron Transport and Ion Acceleration in a Low power Cylindrical Hall Thruster written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Conventional annular Hall thrusters become inefficient when scaled to low power. Cylindrical Hall thrusters, which have lower surface-to-volume ratio, are therefore more promising for scaling down. They presently exhibit performance comparable with conventional annular Hall thrusters. Electron cross-field transport in a 2.6 cm miniaturized cylindrical Hall thruster (100 W power level) has been studied through the analysis of experimental data and Monte Carlo simulations of electron dynamics in the thruster channel. The numerical model takes into account elastic and inelastic electron collisions with atoms, electron-wall collisions, including secondary electron emission, and Bohm diffusion. We show that in order to explain the observed discharge current, the electron anomalous collision frequency [nu][sub B] has to be on the order of the Bohm value, [nu][sub B] [approx] [omega][sub c]/16. The contribution of electron-wall collisions to cross-field transport is found to be insignificant. The plasma density peak observed at the axis of the 2.6 cm cylindrical Hall thruster is likely to be due to the convergent flux of ions, which are born in the annular part of the channel and accelerated towards the thruster axis.
Download or read book Electron Cross field Transport in a Miniaturized Cylindrical Hall Thruster written by Raitses Yevgeny Smirnov Artem (Fisch Na) and published by . This book was released on 2005 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Conventional annular Hall thrusters become inefficient when scaled to low power. Cylindrical Hall thrusters, which have lower surface-to-volume ratio, are more promising for scaling down. They presently exhibit performance comparable with conventional annular Hall thrusters. The present paper gives a review of the experimental and numerical investigations of electron crossfield transport in the 2.6 cm miniaturized cylindrical Hall thruster (100 W power level). We show that, in order to explain the discharge current observed for the typical operating conditions, the electron anomalous collision frequency {nu}{sub b} has to be on the order of the Bohm value, {nu}{sub B} {approx} {omega}{sub c}/16. The contribution of electron-wall collisions to cross-field transport is found to be insignificant. The optimal regimes of thruster operation at low background pressure (below 10{sup -5} Torr) in the vacuum tank appear to be different from those at higher pressure ({approx} 10{sup -4} Torr).
Download or read book Controlling the Plasma Flow in the Miniaturized Cylindrical Hall Thruster written by and published by . This book was released on 2008 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: A substantial narrowmg of the plume of the cylindrical RaIl thruster (CRT) was observed upon the enhancement of the electron emission from the hollow cathode discharge, which implies the possibility for the thruster efficiency increase due to the ion beam focusing. It is demonstrated that the miniaturized CRT can be operated in the non-self-sustained regime, with the discharge current limited by the cathode electron emission. The thruster operation in this mode greatly expands the range of the plasma and discharge parameters normally accessible for the CRT.
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 Electron Cross field Transport in a Low Power Cylindrical Hall Thruster written by and published by . This book was released on 2004 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Conventional annular Hall thrusters become inefficient when scaled to low power. Cylindrical Hall thrusters, which have lower surface-to-volume ratio, are therefore more promising for scaling down. They presently exhibit performance comparable with conventional annular Hall thrusters. Electron cross-field transport in a 2.6 cm miniaturized cylindrical Hall thruster (100 W power level) has been studied through the analysis of experimental data and Monte Carlo simulations of electron dynamics in the thruster channel. The numerical model takes into account elastic and inelastic electron collisions with atoms, electron-wall collisions, including secondary electron emission, and Bohm diffusion. We show that in order to explain the observed discharge current, the electron anomalous collision frequency [nu][sub B] has to be on the order of the Bohm value, [nu][sub B] [approx] [omega][sub c]/16. The contribution of electron-wall collisions to cross-field transport is found to be insignificant.
Download or read book Journal of Applied Physics written by and published by . This book was released on 2003 with total page 500 pages. Available in PDF, EPUB and Kindle. Book excerpt:
