Download or read book Thermal Characterization of a Hall Effect Thruster written by Alex M. Bohnert and published by . This book was released on 2008 with total page 178 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The thermal characteristics of a Hall thruster directly influence thruster and spacecraft design. High temperatures affect the magnetic coil capabilities and cause higher insulator erosion rates, influencing both thruster performance and lifetime. The Hall thruster transfers heat through both radiation and conduction, and the spacecraft must handle this additional thermal energy. An infrared camera provides a non-intrusive method to analyze the thermal characteristics of an operational Hall thruster. This thesis contains the thermal analysis of a Busek Co. Inc. 200 W Hall thruster, using a FLIR ThermaCAM SC640 infrared camera. The Space Propulsion Analysis and System Simulator Laboratory at the Air Force Institute of Technology on Wright-Patterson Air Force Base provided the location for thruster set up and operation. The infrared camera furnishes the surface temperatures for the entire thruster, and approximates the transient heating behavior during start up, steady state, and shut down. Thermocouples verify and correct the camera data. Experimentally determined emissivities characterize the materials of the thruster. In addition, a view factor analysis between the camera pixels and the alumina sprayed portion of the cathode determines the exchange of radiation between the pixels and cathode surface. This process develops a technique to map surface temperatures of complex geometries with confidence in the actual values. Accurately mapping the surface temperatures of a Hall Effect thruster will improve both thruster efficiency and lifetime, and predict the thruster's thermal load on a satellite."--Report documentation page.
Download or read book Characterization of a Hall Effect Thruster Using Thermal Imaging written by James William Tomaszewski and published by . This book was released on 2007 with total page 148 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 Thermal Characterization of a NASA 30 cm Ion Thruster Operated Up to 5 KW written by Timothy R. SarverVerhey and published by . This book was released on 2001 with total page 14 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermographic Characterization and Comparison of 200W and 600W Hall Thrusters Preprint written by and published by . This book was released on 2007 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermal analysis of Hall thrusters is necessary for both performance optimization and spacecraft integration. The thermal characteristics of the thruster influence the lifetime, energy losses, and spacecraft integration. The lifetime of most Hall thrusters is limited by the erosion of the insulating materials within the discharge chamber, which may vary with temperature. Thruster thermal data are also indicative of thruster energy losses as well as the heating characteristics of spacecraft interface surfaces. The results of the thermographic imaging of two laboratory Hall thrusters, a 200W (BusekBHT-200-X3) and 600W (BusekBHT-600), are presented. Surface temperature profiles were obtained using an infrared camera (7-13 micrometres), independently verified by thermocouples. Infrared imagery of thruster start-up, steady-state, and shut-down was recorded and used to approximate the transient heating behavior of each thruster. Variation of the nominal mass flow rate (resulting in proportional variation of the anode current and power level) between 85% to 115% resulted in proportional changes to the thruster surface temperatures.
Download or read book THERMAL CHARACTERIZATION OF A NASA 30 CM ION THRUSTER OPERATED UP TO 5 KW NASA TM 2001 210696 JUN 20 2001 written by 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 Thermographic Characterization and Comparison of 200W and 600W Hall Thruster Postprint written by and published by . This book was released on 2007 with total page 22 pages. Available in PDF, EPUB and Kindle. Book excerpt: Thermal analysis of Hall thrusters is necessary for both performance optimization and spacecraft integration. The thermal characteristics of the thruster influence the lifetime, energy losses, and spacecraft integration. The lifetime of most Hall thrusters is limited by the erosion of the insulating materials within the discharge chamber, which may vary with temperature. Thruster thermal data are also indicative of thruster energy losses as well as the heating characteristics of spacecraft interface surfaces. The results of the thermographic imaging of two laboratory Hall thrusters, a 200W (BusekBHT-200-X3) and 600W (BusekBHT-600), are presented. Surface temperature profiles were obtained using an infrared camera (7-13 microns), independently verified by thermocouples. Infrared imagery of thruster start-up, steady-state, and shut-down was recorded and used to approximate the transient heating behavior of each thruster. Variation of the nominal mass flow rate (resulting in proportional variation of the anode current and power level) between 85% to 115% resulted in proportional changes to the thruster surface temperatures.
Download or read book Preliminary Plume Characterization of a Low Power Hall Thruster Cluster written by and published by . This book was released on 2002 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt: In an effort to understand the technical issues related to running multiple Hall effect thrusters in close proximity to each other, testing of a cluster of four Busek BHT-200-X3 devices has begun in Chamber 6 at the Air Force Research Laboratory. Preliminary measurements have shown that the variations in the discharge currents of the four thrusters are synchronized, possibly due to cross talk through the thruster plumes. Measurements of plasma density, electron temperature, and plasma potential in the thruster plumes obtained using a triple Langmuir probe are presented. Anomalously high electron temperatures were recorded along the centerline of each thruster. Collisionless, magnetosonic shock waves induced by the ion-ion two-stream instability are proposed as a possible cause of the high temperatures. The unperturbed ion velocity distribution along the centerline of a Hall thruster is shown to be unstable and a simple geometric model is presented to illustrate the qualitative changes in plasma properties expected across the proposed shock. Estimates using this model show that relatively large changes in electron temperature are consistent with small changes in electron number density across a shock. Qualitative arguments are presented indicating that collisionless shocks are unlikely to form as a result of clustering multiple thrusters. In an effort to understand the technical issues related to running multiple Hall effect thrusters in close proximity to each other, testing of a cluster of four Busek BHT-200-X3 devices has begun in Chamber 6 at the Air Force Research Laboratory. Preliminary measurements have shown that the variations in the discharge currents of the four thrusters are synchronized, possibly due to cross talk through the thruster plumes. Measurements of plasma density, electron temperature, and plasma potential in the thruster plumes obtained using a triple Langmuir probe are presented.
Download or read book Hall Thruster Ion Beam Characterization written by David H. Manzella and published by . This book was released on 1995 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Development and Characterization of High efficiency High specific Impulse Xenon Hall Thrusters written by Richard Robert Hofer and published by . This book was released on 2004 with total page 808 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Performance Characterization of a Three axis Hall Effect Thruster written by Spencer E. Temkin and published by . This book was released on 2010 with total page 0 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 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 Arcjet Plasma Neutralization of Hall Thrusters I Hybrid Thruster Mission Analysis written by and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Clustering multiple thrusters has emerged as a favored option for extending Hall effect thruster propulsion to very high powers (100-150 kW) for a variety of Air Force missions. However, there are inherent difficulties in the simultaneous neutralization of several Hall effect thrusters. Chief among these is the issue of unequal current sharing among multiple cathodes. For this reason, it may prove advantageous to use a single, high current neutralizer. Conventional Hall effect thruster neutralizers, hollow cathodes, typically consume 10% of the propellant flow and produce little or no thrust. An arcjet is an electro-thermal electric thruster with moderate efficiency and specific impulse ranges. It is also a high plasma density device that is capable of supporting and amplifying electron current through volume ionization and is capable of neutralizing single or clusters of Hall effect thrusters. By using an arcjet as a neutralizer, Hall effect thrusters will also produce useful thrust from their neutralizers. Because of the arcjet's lower specific impulse, the hybrid arcjet-Hall system will have a lower specific impulse than that of a pure Hall effect system. However by choosing suitable propellants, the hybrid Hall cluster will retain the high thrust efficiencies typical of pure Hall effect systems with the added benefit of lower total wet mass for select missions due to a higher system thrust density. This work examines the application of an arcjet-neutralized cluster of Hall effect thrusters for a low earth orbit to geosynchronous orbit transfer. The analysis shows that hybrid Hall effect clusters neutralized by a single medium power arcjet are advantageous for some orbit raising missions. Helium arcjet-neutralizers coupled with conventional xenon Hall effect anodes appear to he the superior configuration due to their relatively high efficiencies and low tankage fractions when compared to alternative propellant mixes.
Download or read book Code de commerce et lois commerciales usuelles par Emile Cohendy written by and published by . This book was released on 1892 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Download or read book Thermomagnetic Convective Cooling of Hall Effect Thruster written by and published by . This book was released on 2018 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract : This work proposes and shows that thermomagnetic convection could be used in zero gravity to cool components of a Hall-effect thruster. A ferrofluid cavity was develop in the thermal and geometric model of a Hall-effect thruster. Simulations show that with an Ionic Liquid Ferrofluid after two minutes of thruster operations thermomagnetic convection occurs and in zero gravity will produce a larger velocity then natural convection that occurs in earth gravity. However, experiments did not result in heat transfer enhancement due to the limitation of the ferrofluid. Replacement of the Ferrotec EFH1 dispersant with dodecylbenzene did not result in Ionic Liquid Ferrofluid equivalent ferrofluid and did not lower of vapor pressure as intended and limited test to 60 °C. This limitation did not allow for the fluid to experience the largest difference in magnetic susceptibility that occurs near the Curie temperature.
Download or read book Thermal Analysis of a Stationary Plasma Thruster written by S. Roche and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
