In collaboration with the Space Electronics working group at the Technische Hochschule Mittelhessen, SPARC Industries sàrl is working on efficient, industry-compatible forecasting tools in order to be able to analyse life-limiting effects of electric engines as accurately as possible and thus ensure more robust designs.
In many cases, effects at the interface between the engine and space cannot be described separately from the processes inside the engine. For accurate modelling and prediction, upstream and downstream mechanisms must be considered as an interconnected system.
This is precisely where the collaboration between SPARC Industries and THM begins – merging advanced plasma physics modelling with the time efficiency and accuracy suitable for industry. The focus is on the RF discharge process in gridded ion thrusters which is of central importance for the simulative prediction of erosive and ultimately lifetime-limiting phenomena in the acceleration stage of the thruster.
The diagrams below show the widening of a single aperture in the acceleration grid after different operating times of the engine. The left image shows the contour after a few hundred hours, the right shows the eroded contour after a few thousand hours of operation. The widening of the effective diameter causes a decrease in the background density of the fuel gas (see colour scale), disrupting optimal RF discharge conditions. This degradation reduces thruster efficiency unless compensated – for example by increasing propellant flow, which in turn increases the mission’s overall fuel consumption.
