Experimental data collected over the last decade show that the start-up Is the most critical phase In FEEP thruster operation. The first wetting or the emitter slit surfaces by the Uquld aeslum Is or paramount Importance In order to obtain a high-quallty emission, i.e. a homogeneous distribution or emission sites along the sllt length. Start-up behaviour may be affected by residual atmosphere pressure and composition and by cleaning, storage and baking procedures. Test activities at CENTROSPAZIO have been thus oriented towards the investigation or the starting characteristics or FEEP emitters as a function or the background pressure, the emitter baking procedure and the emitter slit height, with the main objective or obtaining a better Insight to those aspects or thruster operation related to pre-rllght preparation. Several combinations or the above parameters were selected to test the emitter behaviour In both continuous and pulsed mode. A large number of current I voltage curves were recorded In both modes, showing that the pulsed mode characteristic curves, recorded at 1 Hz with 50 % duty cycle, quite closely follow the corresponding ones In continuous mode; moreover, it was shown possible to switch over from continuous to pulsed operation mode, at any tlme, without any significant deterioration In performance or loss or reproducibility or the characteristics.
Experimental Performance of Continuous and Pulsed FEEP Thrusters
MARCUCCIO, SALVO;ANDRENUCCI, MARIANO
1993-01-01
Abstract
Experimental data collected over the last decade show that the start-up Is the most critical phase In FEEP thruster operation. The first wetting or the emitter slit surfaces by the Uquld aeslum Is or paramount Importance In order to obtain a high-quallty emission, i.e. a homogeneous distribution or emission sites along the sllt length. Start-up behaviour may be affected by residual atmosphere pressure and composition and by cleaning, storage and baking procedures. Test activities at CENTROSPAZIO have been thus oriented towards the investigation or the starting characteristics or FEEP emitters as a function or the background pressure, the emitter baking procedure and the emitter slit height, with the main objective or obtaining a better Insight to those aspects or thruster operation related to pre-rllght preparation. Several combinations or the above parameters were selected to test the emitter behaviour In both continuous and pulsed mode. A large number of current I voltage curves were recorded In both modes, showing that the pulsed mode characteristic curves, recorded at 1 Hz with 50 % duty cycle, quite closely follow the corresponding ones In continuous mode; moreover, it was shown possible to switch over from continuous to pulsed operation mode, at any tlme, without any significant deterioration In performance or loss or reproducibility or the characteristics.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.