Author: United States. Patent and Trademark OfficePublisher:
ISBN:
Category : Patents
Languages : en
Pages : 1530
Book Description
Official Gazette of the United States Patent and Trademark Office
Author: United States. Patent and Trademark OfficePublisher:
ISBN:
Category : Patents
Languages : en
Pages : 1530
Book Description
Official Gazette of the United States Patent and Trademark Office
Author: Energy Research Abstracts
Author: Evaluation of Pulsed Plasma Thruster Micropulsing
Author: National Aeronautics and Space Administration (NASA)Publisher: Createspace Independent Publishing Platform
ISBN: 9781721668700
Category :
Languages : en
Pages : 30
Book Description
This paper evaluates the concept of pulsed plasma thruster (PPT) micropulsing. Micropulsing was a premise behind a power processing unit (PPU) and an energy storage unit (ESU) design that for certain mission profiles, it was advantageous to operate a PPT at lower energy but higher frequency rather than at a higher energy but lower frequency. This premise allows for reductions in the ESU volume and mass without paying a penalty in thrust. To complete the evaluation, an independent spark plug initiation unit, a high voltage power supply and a variety of mica foil capacitors at 2.6, 5, 10, and 20 capacitance were used to conduct a series of tests on a single PPT to map performance levels of thrust, impulse bit, efficiency and specific impulse over a comparable power range. Testing at NASA Glenn Research Center was conducted with breadboard PPT hardware. The test results showed that operating in the lower energy ESU micropulsing mode produced similar thrust levels to a higher energy ESU operating at high power level. Further testing however showed a reduction in specific impulse and efficiency when the smaller capacitances were used at the highest power levels. This would require more fuel mass for a mission that was predominately high power, potentially negating the ESU mass savings. Therefore, micropulsing is advantageous where most of a mission profile occurs at low power, but retains the ability to conduct high thrust maneuvers when necessary. Arrington, Lynn Glenn Research Center NASA/CR-2004-213209, AIAA Paper 2004-3458, E-14717
Pulsed Plasma Thruster Contamination
Author: Roger Metcalf MyersPublisher:
ISBN:
Category : Collection Plumes
Languages : en
Pages : 12
Book Description
Index of Patents Issued from the United States Patent and Trademark Office
Author: Fundamentals of Electric Propulsion
Author: Dan M. GoebelPublisher: John Wiley & Sons
ISBN: 0470436263
Category : Technology & Engineering
Languages : en
Pages : 528
Book Description
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.
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Author: 
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