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Investigation Of Propellant Inefficiencies In A Pulsed Plasma Thruster
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Book Synopsis Investigation of Propellant Inefficiencies in a Pulsed Plasma Thruster by :
Download or read book Investigation of Propellant Inefficiencies in a Pulsed Plasma Thruster written by and published by . This book was released on 1996 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt: A Pulsed Plasma Thruster (PPT) benefits from the inherent engineering simplicity and reduced tankage fraction gained by storing the propellant as a solid. The solid is converted to the gaseous state during an electric surface discharge. Previous research has concluded that the bulk of the propellant expands gas-dynamically from the chamber at low directed velocity, with possibly as little as 10% ionized and efficiently accelerated to high velocity using electromagnetic forces. The two velocity components result in a low propellant utilization efficiency. Critical to improving the PPT efficiency is preventing the formation of the low-velocity propellant and/or developing a means of accelerating it electromagnetically. In the present work measurements are made of the solid propellant conversion to the gaseous state with the intent of better understanding the formation process. By better understanding the propellant conversion it is hoped that future PPTs can be designed with significantly increased propellant efficiencies.
Book Synopsis Basic Research in Electric Propulsion. Part I: Pulsed Plasma Thruster Propellant Efficiency and Contamination. Part II: Arcjet Remote Plume Measurement and Hydrogen Density by :
Download or read book Basic Research in Electric Propulsion. Part I: Pulsed Plasma Thruster Propellant Efficiency and Contamination. Part II: Arcjet Remote Plume Measurement and Hydrogen Density written by and published by . This book was released on 2002 with total page 54 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pulsed Plasma Thrusters (PPT) have been the major technology under investigation for the Small Satellite Electric Propulsion Thruster Research program. Arcjet technology is also under investigation with Electric Propulsion Space Experiment Optical Signature experiments underway and Multiphoton Laser Induced Fluorescence Measurements of Ground State Atomic Hydrogen have been performed in an arcjet plume. At present PPTs are being tested in the laboratory environment with investigations under way to determine exact inefficiency mechanisms that can be corrected. This work has already identified previously unknown physical behavior in the PPT. The Electric Propulsion Space Experiment is a flight demonstration of a 30 kW ammonia arcjet propulsion system. Optical measurements of the arcjet plume were performed using on-board optical equipment ground observatories and other space platforms. Low power arcjet technology provided definitive work on atomic species plume concentrations in low power hydrogen arcjet plumes. This work applied a flame diagnostic Multiphoton Laser Induced Fluorescence to the excited-state plasma environment to investigate concentration levels of atomic ground-state hydrogen.
Book Synopsis Effect of Propellant Temperature on Efficiency in the Pulsed Plasma Thruster by :
Download or read book Effect of Propellant Temperature on Efficiency in the Pulsed Plasma Thruster written by and published by . This book was released on 2003 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: A pulsed plasma thruster (PPT) benefits from the inherent engineering simplicity-and reduced tankage fraction gained by storing the propellant as a solid. The solid is converted to the gaseous state and accelerated by an electric discharge across the propellant face. Previous research has concluded that as little as 10% of the consumed propellant is converted to plasma and efficiently accelerated. The remaining propellant is consumed in the form of late-time vaporization and particulate emission, creating minimal thrust. Critical to improving the PPT performance is improving the propellant utilization. The present work demonstrates one possible method of increasing the PPT propellant efficiency. By measuring the PPT thrust, propellant consumption, and propellant temperature while varying the power level, duration of the experimental run, and total propellant mass, a correlation is established between decreased propropellant temperature and increased propellant efficiency. The method is demonstrated by performance measurements at 60 W and S W, which show a 25% increase in thrust efficiency, while the propellant temperature decreases from 135 to 42 deg C. Larger increases in the efficiency may be realized on-orbit where operating temperatures are commonly subzero. The dependence of propellant consumption on temperature also creates systematic errors in laboratory measurements with short experimental runs, and orbit analyses where the PPT performance measured at one power level is linearly scaled to the power available on the spacecraft.
Book Synopsis Performance Study on Liquid Propellant Pulsed Plasma Thruster by : Akira Kakami
Download or read book Performance Study on Liquid Propellant Pulsed Plasma Thruster written by Akira Kakami and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Propellant Losses Because of Particulate Emission in a Pulsed Plasma Thruster by :
Download or read book Propellant Losses Because of Particulate Emission in a Pulsed Plasma Thruster written by and published by . This book was released on 1998 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Propellant inefficiency material in particulate form is characterized in a laboratory pulsed plasma thruster (PPT) operating at 1 Hz with a 204 discharge energy (20 W). Exhaust deposits are collected and analyzed using a combination of a scanning electron microscope with energy dispersive x-ray analysis and microscopic imaging. Teflon(trademark) particulates are observed with characteristic dianietens ranging from over 100 micrometers down to less than 1 micrometer.
Book Synopsis Investigation of Thrust Mechanisms in a Water Fed Pulsed Plasma Thruster by : Carsten A. Scharlemann
Download or read book Investigation of Thrust Mechanisms in a Water Fed Pulsed Plasma Thruster written by Carsten A. Scharlemann and published by . This book was released on 2003 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt: Abstract: Analytic models predict the possibility of extending the range of performance parameters of Pulsed Plasma Thrusters (PPT) by using propellants other than the traditionally used Teflon. A theoretical and experimental effort was initiated at The Ohio State University to investigate the use of alternative propellants for PPT. Analytical and numerical calculations (MACH2) indeed indicate a significant broadening of the obtainable range of specific impulse and thrust-to-power ratios when alternative propellants such as lithium or water are utilized. Consequently, in an effort to investigate changes in physical phenomena and thruster performance experimentally, a hybrid thruster was designed and built, facilitating the use of alternatively water or Teflon. The thruster design includes a unique water propellant feed system, allowing the supply of the water propellant without detrimentally affecting the inherent simplicity of the PPT system. ii The thruster operation and performance was investigated by several different diagnostic methods, including current and voltage measurements, Langmuir probes, and magnetic field probes. Furthermore, impact pressure measurements in the plume of the thruster allowed new insight into the plume structure and the accurate evaluation of impulse bits. Employment of the diagnostic methods for Teflon and water propellant enabled the unambigous identification of propellant related effects such as reduced electron temperature and higher exhaust velocites in the case of water propellant. The electromagnetic nature of the water thruster was clearly identified. For 30 J discharge energy, the water thruster requires only 5% of the mass bit of a Teflon thruster to produce an impulse bit 30% of the magnitude of the Teflon thruster, suggesting greatly increased propellant efficiencies. In agreement with the plasma diagnostic results, a specific impulse for the water thruster of up to 8000 s and efficiencies of up to 16% were evaluated.
Book Synopsis Characterization of an Exploding Micro-wire Pulsed Plasma Thruster by : Diego Mejia Montano
Download or read book Characterization of an Exploding Micro-wire Pulsed Plasma Thruster written by Diego Mejia Montano and published by . This book was released on 2019 with total page 64 pages. Available in PDF, EPUB and Kindle. Book excerpt: Pulsed Plasma Thrusters typically live in the low-range efficiency realm compared to other types of electric propulsion thrusters. In an attempt to explore if any added benefits could be gained from experimenting with a new propellant type, additional physics had to be incorporated into the classical RLC model approach. A study into modeling how a micro-wire propellant would react when subjected to energy deposition via current-driven heating was undertaken. Once a first-order estimate, verified with computational estimates, was obtained then the classical RLC series circuit model could be used to compare and validate the results obtained from experimentation. It was found that while the proposed propellant type is feasible, it produced performance differences that could not be explained solely by the classical model and a more exhaustive investigation into various phenomena will have to be pursued.
Book Synopsis The Effect of Propellant Temperature on Efficiency in a Pulsed Plasma Thruster by : Gregory G. Spanjers
Download or read book The Effect of Propellant Temperature on Efficiency in a Pulsed Plasma Thruster written by Gregory G. Spanjers and published by . This book was released on 1997 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Liquid Pulsed Plasma Thruster Plasma Plume Investigation and MR-SAT Cold Gas Propulsion System Performance Analysis by : Jeremiah Daniel Hanna
Download or read book Liquid Pulsed Plasma Thruster Plasma Plume Investigation and MR-SAT Cold Gas Propulsion System Performance Analysis written by Jeremiah Daniel Hanna and published by . This book was released on 2017 with total page 103 pages. Available in PDF, EPUB and Kindle. Book excerpt: "The plasma plume produced by a liquid pulsed plasma thruster is investigated using a Langmuir triple probe and a nude Faraday probe. The Langmuir triple probe failed to produce results which are suspected caused by the presence of ionic liquid in the plume resulting in shorting of the probe. The nude Faraday probe is able to record the ion current density which revealed a high level of inconsistency in the plasma plume. Ion current density recorded by the nude Faraday probe had a relative standard deviation of upwards of 100% of the mean value. Controlling the amount of propellant used during each pulse was extremely difficult. Investigating the plasma plume with more complex probes was not done due to the inconsistency measured by the nude Faraday probe and the expulsion of ionic liquid from the thruster which is highly corrosive to metals. Examining the historical thrust test data performed by the Missouri Satellite Research Team, a revised model with new assumptions was created and resulted in an improvement in accuracy to within 4.5%. The cold gas propulsion system developed over the years had undergone testing which resulted in measured thrust half of what was predicted. Developing a thrust prediction scheme that incorporates the effects of the solenoid control valve decreases the error to between 1-3% depending on temperature considerations. This thrust prediction scheme can be applied to the current design for the NanoSat 8 competition and results in an accurate prediction of thrust"--Abstract, page iii.
Book Synopsis Study of a Dual Stage Solid Propellant Pulsed Plasma Thruster by : Clémence Royer
Download or read book Study of a Dual Stage Solid Propellant Pulsed Plasma Thruster written by Clémence Royer and published by . This book was released on 2018 with total page 107 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Pulsed Plasma Thruster Technology for Small Satellite Missions by :
Download or read book Pulsed Plasma Thruster Technology for Small Satellite Missions written by and published by . This book was released on 1995 with total page 18 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis An Investigation of Stationary Plasma Thruster Performance with Krypton Propellant by : Colleen Marrese
Download or read book An Investigation of Stationary Plasma Thruster Performance with Krypton Propellant written by Colleen Marrese and published by . This book was released on 1995 with total page pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Solid Propellant Pulsed Plasma Micro-thruster Studies by : William J. Guman
Download or read book Solid Propellant Pulsed Plasma Micro-thruster Studies written by William J. Guman and published by . This book was released on 1968 with total page 10 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Breakthrough to Optimized Pulsed Plasma Thrusters by :
Download or read book Breakthrough to Optimized Pulsed Plasma Thrusters written by and published by . This book was released on 2004 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Analytic models predict the possibility of extending the range of performance parameters of Pulsed Plasma Thrusters (PPT) by using propellants other than the traditionally used Teflon. A theoretical and experimental effort was initiated at The Ohio State University to investigate the use of alternative propellants for PPT. Analytical and numerical calculations (MACH2) indeed indicate a significant broadening of the obtainable range of specific impulse and thrust-to-power ratios when alternative propellants such as lithium or water are utilized. Consequently, in an effort to investigate changes in physical phenomena and thruster performance experimentally, a hybrid thruster was designed and built, facilitating the use of alternatively water or Teflon. The thruster design includes a unique water propellant feed system, allowing the supply of the water propellant without detrimentally affecting the inherent simplicity of the PPT system. The thruster operation and performance was investigated by several different diagnostic methods, including current and voltage measurements, Langmuir probes, and magnetic field probes. Furthermore, impact pressure measurements in the plume of the thruster allowed new insight into the plume structure and the accurate evaluation of impulse bits. Employment of the diagnostic methods for Teflon and water propellant enabled the unambiguous identification of propellant related effects such as reduced electron temperature and higher exhaust velocities in the case of water propellant.
Book Synopsis Fundamentals of Electric Propulsion by : Dan M. Goebel
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.
Book Synopsis A Performance Comparison of Pulsed Plasma Thruster Electrode Configurations by :
Download or read book A Performance Comparison of Pulsed Plasma Thruster Electrode Configurations written by and published by . This book was released on 1997 with total page 16 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Book Synopsis Transport Processes in Pulsed Plasma Thrusters by :
Download or read book Transport Processes in Pulsed Plasma Thrusters written by and published by . This book was released on 1997 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: The simplicity of the pulsed plasma microthruster (PPT) allowed its selection for space flight application, even with low efficiency relative to other concepts. Improvements to PPT thrust efficiency and specific impulse represent today's challenges for research and development. Self consistent modeling of PPT behavior requires a description of the flow composition as it changes from complex molecular forms to highly ionized, constituent atoms. Heat flux from the plasma discharge to the solid propellant, (traditionally, Teflon), depends on transport coefficients for electrical and thermal conductivity in the partially ionized flow. Numerical simulations now use an existing, single temperature equation of state for Teflon (from the SESAME tables) along with classical transport formulas based on Coulomb collisions. The principal effort under the present grant has been to develop a two-temperature, LTE model for Teflon in the regime of interest for PPTs. This model includes 25 species (atoms, molecules, ions and electronics) and allows separates heavy-particle and electron temperatures. An idealized analysis, limited to one-dimensional, quasi-steady MHD flow, but incorporating resistive heating and thermal diffusion, has also been developed and provides useful guidance on PPT operation and propellant behavior.
