ESA Open Invitation to Tender: 1-10844
Open Date: 09/07/2021 08:24 CEST
Closing Date: 20/08/2021 13:00 CEST

The use of electric propulsion on-board satellites requires careful assessment of thruster-spacecraft interactions by means of numerical simulations. The numerical tools used for these simulations (e.g. SPIS Spacecraft Plasma Interaction System) are mostly based on hybrid plume models. This is in line with the needs from industry in terms of model complexity and computational time.Despitethe fact that an accurate description of the electron cooling is important in order to correctly reproduce the plasma electric potential, electron models used for the fluid description are often too simplistic and hence not physically justified for the near-collision less plume. In order to derive an electron thermodynamic model with good physical grounds, a full kinetic treatment of the electron population is essential. In a previous ESA TRP study (T719-402MP), the open-source AKILES kinetic model was developed to derive physically robust laws for electron cooling and electrostatic potential in the thruster far-field plume. The AKILES kinetic model however relies on a number of analytical assumptions and is only quasi-1D. This activity will focus on the derivation of electroncooling laws. The activity encompasses the following tasks:- Develop a 2D full particle model of the expansion of a divergent current-free plasma plume for the determination of electron cooling laws covering both the near-field and the far-field region of the plume.- Perform an extensive test campaign to gather experimental data using at least a low power gridded ion engine and if possible another low power EP thruster (HET or other) for the validation of the 2D model.- Investigate the facility effects (especially background pressure but also influence of chamber walls) on electron kinetics in order to determine the effect on ground measurementsand to get better a extrapolation of results to space conditions.- Use the 2D full particle model to define macroscopic, simplified electron cooling laws that can be implemented in spacecraft-plasma interaction modelling tools such as SPIS.

Directorate: Directorate of Tech, Eng. Quality
Estabilishment: ESTEC
ECOS Required: No
Classified: No
Price Range: 200-500 KEURO
Authorised Contact Person: Rudolfo Almeida
Initiating Service: TEC-MPE
IP Measure: N/A
Prog. Reference: E/0901-01 – Technology Developme
Tender Type: Open Competition
Open To Tenderers From: AT+BE+CH+CZ+DE+DK+EE+EL+ES+FI+FR+GB+HU+IE+IT+LU+NL+NO+PL+PT+RO+SE
Technology Keywords: 16-B-II-Micro-Optics Components, MOEMS, Optical Fibres and Passive Integrated Optics
Products Keywords: 1-A-4-a-IMU, IMU/GPS *See Software