Documents / Report
This Defense Intelligence Agency reference document, dated 1 November 2010, is one of a series of advanced technology reports produced in FY 2010 under the Advanced Aerospace Weapons System Applications (AAWSA) Program. It covers fusion plasma physics, confinement methods, and propulsion concepts that use aneutronic fuels such as hydrogen and boron-11. It concludes that such thrusters may soon replace satellite ion thrusters. It also finds that they will not be practical beyond the solar system without breakthrough propulsion physics.
“The Advance”7 pages
UNCLASSIFIED//F81il 8FFI1il.t.k Wfili 8Hklf Chapter 4: Applications NEAR SPACE Although aneutronic fusion thrusters will not be able to achieve liftoff for single-stage orbit vehicles as discussed in Chapter 3 above Mach 14, they can provide the necessary thrust to insert an air vehicle into orbit. In fact, any vehicle in orbit could benefit from such a propulsion device to dip down and maneuver in the atmosphere and return to orbit with the aid of fusion propulsion as long as it does not slow below Mach 14. This capability will allow a host of missions that include the following: • Antisatellite threat avoidance. • Unpredictable Earth or space target reconnaissance. • Unpredictable Earth or space target neutralization. The details of such applications will be the subject of separate studies. Undoubtedly current propulsion technologies are significantly limited in N/kW in propulsion capability to perform such missions for long durations. However, they may be sufficient due to the threats and targets needed to be countered at this time. EARTH ORBIT Space thrusters for orbital insertion and station keeping have been using hydrazine propellant and, more recently for large GEO satellites, arc jet thrusters, which electrostatically enhance the hydrazine propellant. High-power Hall Current Thrusters (HCT) that electrostatically accelerate Xe ions have been developed by NASA with discharge power levels ranging from 6.4 kilowatts to 72.5 kilowatts. 16 Such devices produce thrust ranging from 0.3 to 2.5 Newtons and specific impulses up to 4,500 seconds at 1 kV. More recently, AeroJet together with Lockheed Martin Space Systems Company have qualified a 4. 5-kW Hall Thruster Propulsion System (HTPS) that demonstrated 244 mN of thrust with a specific impulse of 1,981 seconds incorporating a 400-volt acceleration potential. These thrusters were flown in 2010 on military communication and surveillance satellites. Expected enhancements of these HCTs will provide higher lsp near 3,000 seconds at the expense of significant lower thrust, ~10 mN/kW. Future broadband communication commercial and military satellites of 20- to 50-kW broadcast power will require much more efficient thruster performance in terms of mN/kW in order to satisfy the operational performance needs of their solar power systems. This provides the motivation for the development of aneutronic fusion enhanced ion thrusters. Such a development has been proposed by transforming a conventional ion thruster into a spherical form. 17 Using the IEC configuration shown in Figure 13, ions are produced in the gas discharge region through the injection and oscillation of electrons about a guide grid that is held to a slightly positive potential. The grid extracts ions from the discharge region and accelerates them toward the center of the device. It is estimated to provide 35 mN of thrust for 750 watts of input power at 500 volts, providing an lsp of 3,000 seconds or 45 mN/kW superior to the advanced HCT thrusters. The addition of a 150-kWe ion beam for heating a (p, 11 B) plasma close to ignition (Q~ 1) using a magnetic guide system to redirect the nearly isotopic velocity distribution of 17 UNCLASSIFIED/ /PSR: err1e1111t ~!H! SHLY
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Report, from the dia collection. The PDF is mirrored here; the original link is above. 36 pages are in the text index: search them above, or from the library's search.