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Thermal stability of the krypton Hall effect thruster

Szelecka A., Kurzyna J., Bourdain L.

Nukleonika

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2017

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Vol. 62, No. 1

9--15

EN

The Krypton Large IMpulse Thruster (KLIMT) ESA/PECS project, which has been implemented in the Institute of Plasma Physics and Laser Microfusion (IPPLM) and now is approaching its final phase, was aimed at incremental development of a ~500 W class Hall effect thruster (HET). Xenon, predominantly used as a propellant in the state-of-the-art HETs, is extremely expensive. Krypton has been considered as a cheaper alternative since more than fifteen years; however, to the best knowledge of the authors, there has not been a HET model especially designed for this noble gas. To address this issue, KLIMT has been geared towards operation primarily with krypton. During the project, three subsequent prototype versions of the thruster were designed, manufactured and tested, aimed at gradual improvement of each next exemplar. In the current paper, the heat loads in new engine have been discussed. It has been shown that thermal equilibrium of the thruster is gained within the safety limits of the materials used. Extensive testing with both gases was performed to compare KLIMT’s thermal behaviour when supplied with krypton and xenon propellants.

2

Liquid micro pulsed plasma thruster

Szelecka A., Kurzyna J., Daniłko D., Barral S.

Nukleonika

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2015

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Vol. 60, No. 2

257--261

EN

A new type of pulsed plasma thruster (PPT) for small satellite propulsion is investigated, of which the most innovative aspect is the use of a non-volatile liquid propellant. The thruster is based on an open capillary design. The thruster achieved a thrust-to-power ratio above 45 μN/W, which constitutes a 5-fold improvement over the water-propelled pulsed plasma thruster, and which is also slightly above the performance of a similarly sized PPT with a solid propellant.

3

Current and plasma oscillation characterization in a PPS®-X000 Hall-effect thruster

Kurzyna J., Makowski K., Peradzyński Z., Lazurenko A., Mazouffre S., Coduti G., Dudeck M.

Journal of Technical Physics

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2008

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Vol. 49, no 3-4

267-282

EN

The correlations between local plasma oscillations and the discharge current or cathode potential variations are studied in a high-voltage Hall-effect thruster (HET). A set of electric probes is used to collect the signals. The probes are located in the exhaust region of the thruster, beyond its outer circumference. Measurements are performed for various probe positions and bias potentials, within a wide range of thruster operating conditions. The non-stationary signals are subsequently expanded into finite sets of intrinsic modes with the use of the Empirical Mode Decomposition (EMD) method. The Hilbert-Huang power spectra indicate characteristic bands in the low frequency (LF, tens of kHz), medium frequency (MF) and high frequency (HF, tens of MHz) range. However, the regular HF emission that has been observed in our previous low-voltage characterization of a PPS-100 thruster, is only observable in some particular operating conditions. When the supply voltage is low (e.g. 400 V), the known electrostatic drift wave propagating along the thruster azimuth is unambiguously identified in the probe signals. For higher voltages, HF spectra are usually broadband and do not highlight well the defined peaks. HF emission becomes very irregular or even seemingly random. On the other hand, when regular waves appear (intermittently or in series of bursts), frequencies in the ss 5-100 MHz band can be observed. The oscillations within the MF band that were previously weak in the PPS-100 thruster, appear now to dominate the discharge current spectrum when the thruster operates at the highest voltages. Intense oscillations in the MF range are identified with the use of positively biased probes and by examination of the cathode potential and discharge current variations. The correlations of all the mentioned signals are clear in this frequency band. Correlating the oscillations in the HF band with the MF discharge current wave, one can deduce that HF oscillations are periodically triggered by MF waves at high voltage, while at lower voltage they are triggered by the LF breathing mode, as previously observed in the case of the PPS-100 thruster.

4

Monitorowanie jakości spoiny podczas spawania laserowego

Hoffman J., Kurzyna J., Szymański Z., Jakubowski J., Kolasa A.

Krzepnięcie Metali i Stopów

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2000

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R. 2, nr 42

309--317

PL

Spawanie laserowe stosowane jest w celu uzyskania połączeń wysokiej jakości. Szczególnego znaczenia nabiera więc kontrola jakości spoiny. Kontrola wykonywana po spawaniu wydłuża proces technologiczny nie umożliwiając korekty parametrów spawania na bieżąco , tj. w trakcie spawania. Dlatego poszukiwane są metody, które dzięki analizie rejestrowanych sygnałów pozwalałyby na ocenę jego jakości podczas procesu. Proponowane są metody oparte na pomiarach promieniowania własnego plazmy powstającej przy spawaniu, promieniowania lasera pomiarowego odbitego od jeziorka spawalniczego, rejestracji sygnałów akustycznych generowanych podczas spawania itp. [...]