Thrust enhancement of the gasdynamic mirror (GDM) fusion propulsion system

Journal Article · Fri Jan 10 04:00:00 EST 1997 · AIP Conference Proceedings

DOI:https://doi.org/10.1063/1.51966· OSTI ID:21165717

Kammash, Terry; Lee, Myoung-Jae; Poston, David I ^[1]

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1. Department of Nuclear Engineering and Radiological Sciences, University of Michigan Ann Arbor, Michigan 48109 (United States)

The gasdynamic mirror propulsion system is a device that utilizes a magnetic mirror configuration to confine a hot plasma to allow fusion reactions to take place while ejecting a fraction of the energetic charged particles through one end to generate thrust. Because the fusion fuel is generally an isotope of hydrogen, e.g., deuterium or tritium, this propulsion device is capable of producing very large specific impulses (e.g., 200,000 seconds) but at modest thrusts. Since large thrusts are desirable, not only for reducing travel time but also for lifting sizable payloads, we have examined methods by which GDM's thrust could be enhanced. The first consists of utilizing the radiation generated by the plasma, namely bremsstrahlung and synchrotron radiation, to heat a hydrogen propellant which upon exhausting through a nozzle produces the additional thrust. We asses the performance in this case by using an ideal model that ignores heat transfer considerations of the chamber wall, and one that takes into account heat flow and wall temperature limitations. We find in the case of a DT burning plasma that although thrust enhancement is significant, it was more than offset by the large drop in the specific impulse and a concomitant increase in travel time. The second method consisted of not altering the original GDM operation, but simply increasing the density of the injected plasma to achieve higher thrust. It is shown that the latter approach is more effective since it is compatible with improved performance in that it reduces trip time but at the expense of larger vehicle mass. For a D-He{sup 3} burning device the use of hydrogen to enhance thrust appears to be more desirable since the radiated power that goes into heating the hydrogen propellant is quite large.

• OSTI ID: 21165717
• Journal Information: AIP Conference Proceedings, Journal Name: AIP Conference Proceedings Journal Issue: 1 Vol. 387; ISSN APCPCS; ISSN 0094-243X
• Country of Publication: United States
• Language: English

Related Subjects

70 PLASMA PHYSICS AND FUSION TECHNOLOGY
D-T OPERATION
DEUTERIUM
HEAT FLUX
HEAT TRANSFER
HELIUM 3
HOT PLASMA
HYDROGEN
MAGNETIC MIRROR CONFIGURATIONS
MAGNETIC MIRRORS
OPERATION
PROPULSION SYSTEMS
PULSES
SPACE VEHICLES
SYNCHROTRON RADIATION
THERMONUCLEAR FUELS
TRITIUM