The Air Force Clustered Hall Thruster Program

Abstract

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The Effects of Cathode Configuration on Hall Thruster Cluster Plume Properties

“…6,7 First, the basic operational characteristics of each thruster using a shared cathode depend on whether or not adjacent thrusters are running. This means that there are likely to be cases where a cluster will 4 Walker used the 5-kW P5 thruster, Zakharenkov, et al used a cluster of three 1.5-kW D-55 anode layer thrusters. …”

“…First, since thrust was not measured as part of the present investigation, one could hypothesize that the definitive changes in plasma potential, electron temperature, and plasma density profiles discussed above occurred without being accompanied by a change in performance. Second, since both Walker 18 and Zakharenkov, et al, 19 studied larger thrusters, 4 it might be reasonable to suppose that larger thrusters are in some way less sensitive to cathode location than the 200-watt engines studied here. Third, it is possible to hypothesize that there may be a particular design feature (not related to power level) that makes particular thrusters more or less sensitive to cathode position.…”

“…1,2 In an effort to understand the technical issues related to operating multiple Hall thrusters in close proximity to each other, a cluster of four Busek BHT-200-X3 200-watt class devices has been studied in detail and reported on previously. [3][4][5][6][7] A cluster of thrusters may have a slightly lower efficiency and higher dry mass than a single, similarly powered thruster since larger engines have historically outperformed smaller thrusters. In contrast to this slight potential disadvantage in performance, however, recently published work has concluded that a cluster also offers several advantages over a monolithic thruster.…”

Laser-Induced Fluorescence of Neutral Xenon in the Near Field of a 200 W Hall Thruster

“…The Hall thruster is the Busek Company BHT-200-X3 200 W Hall thruster which has been described elsewhere [5]. Table 1 shows the nominal operating conditions for the BHT-200-X3 thruster for this test.…”

Preliminary Plume Characterization of a Low-Power Hall Thruster Cluster

“…4 A cluster of thrusters may have a slightly lower efficiency and higher dry mass than a similarly powered monolithic thruster since larger thrusters have historically performed better than smaller thrusters. However, the clustered approach does have several advantages, including improved system reliability due to the inherent redundancy of running multiple engines, as well as the ability to throttle the system by simply turning off one or more of the thrusters.…”