Download or read book Modeling of Ablation fed Pulsed Plasma Thrusters written by Peter J. Turchi and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Theoretical Modeling and Optimization of Ablation fed Pulsed Plasma Thrusters written by Yiangos George Mikellides and published by . This book was released on 1999 with total page 106 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Theoretical modeling of ablation-fed, pulsed plasma thrusters (PPTs) with the MACH2 code has shown that after repeated pulsed operation, the total expelled mass is due to ablation during the discharge and solid decomposition that persists long after the pulse. The latter mass does not considerably contribute to the impulse-bit thus degrading thruster performance. For the rectangular PPT geometry, optimizing current waveforms in combination with channel widths are presented, that utilize all decomposed mass, electromagnetically. These waveforms are characterized by short rise times (1 [mu]sec) and prolonged decays (25 [mu]sec). Simplified modeling based on steady-state, one-dimensional flow reveals that the mass flow rate varies linearly with the square of the magnetic field and that the downstream flow speed is driven towards the Alfven wave speed when the magnetic pressure is much greater than the gasdynamic pressure. The model has been confirmed by MACH2. The mass flow requirement for such magnetosonic flow in turn, determines the surface temperature of the solid.

Download or read book Modeling of Late time Ablation in Teflon Pulsed Plasma Thrusters written by P. G. Mikellides and published by . This book was released on 1996 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Transport in Plasma Thrusters Using Complex Propellants written by and published by . This book was released on 2004 with total page 80 pages. Available in PDF, EPUB and Kindle. Book excerpt: Theoretical modeling of ablation-fed, pulsed plasma thrusters (PPTs) with the MACH2 code has shown that after repeated pulsed operation, the total expelled mass is due to ablation during the discharge and solid decomposition that persists long after the pulse. The latter mass does not considerably contribute to the impulse-bit thus degrading thruster performance. For the rectangular PPT geometry, optimizing current waveforms in combination with channel widths are presented, that utilize all decomposed mass, electromagnetically. These waveforms are characterized by short rise times (1 microsec) and prolonged decays (25 micro sec). Simplified modeling based on steady-state, one-dimensional flow reveals that the mass flow rate varies linearly with the square of the magnetic field and that the downstream flow speed is driven towards the Alfven wave speed when the magnetic pressure is much greater than the gasdynamic pressure. The model has been confirmed by MACH2. The mass flow requirement for such magnetosonic flow in turn, determines the surface temperature of the solid.

Download or read book Experiments with Multi material Propellants in Ablation fed Pulsed Plasma Thrusters written by R. J. Leiweke and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Plasma Generation and Application in a Laser Ablation Pulsed Plasma Thruster written by Jianjun Wu and published by . This book was released on 2022 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The laser ablation plasma thruster is a novel electric propulsion thruster, which combined the laser ablation and electromagnetic acceleration. In order to investigate the plasma expansion and ionization in the laser ablation plasma thruster, which was difficult to obtain from experiments, the heat conduction model and fluid dynamics model were established. The heat conduction model was established to calculate the target ablation, taking into account temperature-dependent material properties, phase transition, dielectric transition and phase explosion. The fluid dynamics model was used to calculate the plasma properties, taking into account ionization, plasma absorption and shielding. The ablation plasma velocity, temperature and electron number density were predicted by using the numerical method. The calculated results showed that the peak values of ablation plasma velocity, temperature and electron number density fraction were distributed at the front of the plasma plume. Moreover, the discharge characteristics and thrust performance were tested with different charged energy, structural parameters and propellants. The thrust performance was proven to be improved by electromagnetic acceleration.

Download or read book An Experimental and Theoretical Study Towards Performance Improvements of the Ablation Fed Pulsed Plasma Thruster written by Erik M. Henrikson and published by . This book was released on 2010 with total page 266 pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Numerical Analysis of Transient Teflon Ablation in Pulsed Plasma Thrusters written by and published by . This book was released on 2007 with total page 127 pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: One of the general processes of interest in Pulsed Plasma Thrusters is the ablation of the solid fuel. In general, ablation occurs when a short pulse of applied energy removes a portion of the fuel surface. Although this ablation process is relatively straight-forward in simple materials that sublimate, ablation in Pulsed Plasma Thrusters is significantly more complicated. This is caused by the transient conditions and the complex behavior of Teflon that does not sublimate but rather undergoes both physical and chemical changes prior to leaving the surface. These two effects combine to make Teflon ablation a highly nonlinear function of heat flux, material property variations, changing molecular weight, and phase transformation behavior. To gain greater insight into the ablation process, a one-dimensional ablation model is developed that addresses the more detailed thermal and thermodynamic behavior of Teflon during simulated operation of a Pulsed Plasma Thruster. The mathematical model is based on the work of Clark (1971), which focused on two-phase, one-dimensional Teflon ablation in the context of thermal protection systems. The model is modified for use in simulated PPT operations and implemented numerically using an adaptive non-uniform grid, explicit finite-difference techniques, and a volume fraction method to capture the interface between the crystalline and amorphous Teflon phases. The ablation model is validated against analytical heat transfer and ablation solutions and compared with previous experimental results. The Teflon ablation model is used to analyze several general ablation scenarios in addition to specific PPT conditions to gain greater insight into long-duration thruster firing, post-pulse material ablation, variable heat flux effects, variable material property effects, and the impact of surface re-crystallization on particulate emission. These simulations are considered in the context of prior experimental investigations of Pulsed Plasma Thrusters. The results of these simulations demonstrate the success of the numerical ablation model in predicting experimental trend and suggest potential paths of moderately improving thruster efficiency and operational repeatability in the future.

Download or read book Particle Simulation of Pulsed Plasma Thruster Plumes written by and published by . This book was released on 2002 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: This final report summarizes the research carried out on the development of numerical approaches for simulating the plumes of pulsed plasma thrusters. A significant amount of progress has been made in the three years of this grant and this summarized in the 9 journals and conference papers that are included as appendices to this report. Our modeling had made progress in al aspects of simulating these complex devices including Teflon ablation, plasma formation, electro-magnetic acceleration, plume expansion, and particulate transport. Several different pulsed plasma thruster devices were modeled including an electro-thermal device (the PPT-4 developed at the University of Illinois by Dr. Rod Burton), and various micro-PPT's (developed at the Air Force Research Laboratory by Dr. Greg Spanjers and colleagues).

Download or read book Encyclopedia of Plasma Technology Two Volume Set written by J. Leon Shohet and published by CRC Press. This book was released on 2016-12-12 with total page 1654 pages. Available in PDF, EPUB and Kindle. Book excerpt: Technical plasmas have a wide range of industrial applications. The Encyclopedia of Plasma Technology covers all aspects of plasma technology from the fundamentals to a range of applications across a large number of industries and disciplines. Topics covered include nanotechnology, solar cell technology, biomedical and clinical applications, electronic materials, sustainability, and clean technologies. The book bridges materials science, industrial chemistry, physics, and engineering, making it a must have for researchers in industry and academia, as well as those working on application-oriented plasma technologies. Also Available Online This Taylor & Francis encyclopedia is also available through online subscription, offering a variety of extra benefits for researchers, students, and librarians, including: Citation tracking and alerts Active reference linking Saved searches and marked lists HTML and PDF format options Contact Taylor and Francis for more information or to inquire about subscription options and print/online combination packages. US: (Tel) 1.888.318.2367; (E-mail) [email protected] International: (Tel) +44 (0) 20 7017 6062; (E-mail) [email protected]

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 Review of Micro Propulsion Ablative Devices written by and published by . This book was released on 2004 with total page 31 pages. Available in PDF, EPUB and Kindle. Book excerpt: OUTLINE: * Examples of micro propulsion ablative devices * Fundamentals of ablation * Detailed analysis of specific devices: Micro-Pulsed Plasma Thruster -- Micro-Laser Plasma Thruster -- Micro-Vacuum Arc Thruster * SUMMARY: * Various microthruster technologies based on ablative mechanism were developed. * Self-consistent modeling approach for ablative micro-thrusters was formulated based on a kinetic ablation model and particle plume simulation. * Most extensive validation of the modeling approach was performed for micro-pulsed plasma thruster. Plasma density, surface temperature, ablation rate, ablation profile were compared with experiment. Optimization criteria were formulated for some devices, such as microPPT.

Download or read book High order Modeling of Micro pulsed Plasma Thrusters written by Guang Lin 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 Modeling of a Pulsed Plasma Thruster from Plasma Generation to Plume Far Field written by Iain D. Boyd and published by . This book was released on 1999 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:

Download or read book Dimensionless Performance Model for Gas fed Pulsed Plasma Thrusters written by John K. Ziemer and published by . This book was released on 1998 with total page 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 587 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 Modeling the Exhaust of the Pulsed Plasma Thruster written by D. W. Yannitell and published by . This book was released on 1985 with total page 34 pages. Available in PDF, EPUB and Kindle. Book excerpt: The work presented in this report is an investigation of the plasma flow on a Teflon Pulsed Plasma Thruster (PPT), and the resulting plume. The long range goal is a theoretical model of the flow, both between and beyond the thruster electrodes, that could aid in the improvement of performance, and also predict the contamination potential of the device. The overall model required consists of an internal portion interfaced with an external portion at the exit plane of the electrodes. Most of this report deals with the internal portion of the model. Specifically, the physics of the discharge and plasma acceleration between the electrodes are discussed, and a mathematical model is developed which appears to be consistant with the available experimental data. The investigation shows the necessity of certain additional information without which the model cannot be properly exercised. The validity of certain assumptions of magnetohydrodynamic theory is demonstrated for the nontypical plasma produced by the PPT, and logical consequences of the assumptions are considered vis a vis recently obtained electromagnetic data. A major difficulty in the modeling of the internal flow is the selection of the proper boundary conditions to be applied to the solution domain. These include conditions at the electrodes, the insulator, the ablating Teflon surfaces, and the interface with the vacuum ahead of, and behind, the plasma blobs. Keywords include: Pulsed plasma; Plume modeling; Teflon pulsed plasma.