Plume characteristics of the NEXT thruster have been examined for a substantial number of high thrust to power, low specific impulse operating points that go beyond the standard throttle table. Angular flux profiles were measured in plume near-field and mid-field using two planar probe types. Charge ratios were determined in the mid-field using an E×B probe, with limited axial scans of J~(++) and J~+ to determine distance dependence and aid charge ratio corrections for charge exchange effects. Thrust loss factors due to charge ratio have been calculated for the various operating points, including an extensive series where propellant utilization was varied. The data show good consistency with respect to previous results for the standard throttle table.
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