Speaker
Description
The ESAs Plasma Observatory is a mission that will study plasma energization and energy transport in Earth’s Magnetospheric System. This task is going to be performed by constellation 7 Sister Space Crafts (SSCs) with specialised equipment. The thermal aspects of this mission are of interest of this study.
The most dangerous elements of this mission, from thermal perspective, are raising while in coasting phase (stacked in Ariane 6 ULPM module) and then after deployment in Nominal Science Phase (NSP). While in NSP the SSCs are expected to not only maintain required relative position but also keep constant rotation for payload to operate correctly.
Unfortunately environmental conditions for both mentioned phases are different. During rising the SSC is mounted to hub in ULPM module and will experience cold case with limited heat generation (turned off equipment). This is our cold survival case, where maximum possible insulation from environment would be beneficial.
While in the NSP the SSC is rotating with solar arrays periodically in direct sunlight and shadow. Due to that the preferred thermal solution is the maximum thermal contact of electronical equipment with radiators. Possible tilt of the spacecraft, that would expose top or bottom to sunlight with some inclination, is another difficulty to be tackled, since slight tilting cannot be completely prevented.
To satisfy those opposite needs the thermal trade-off analysis was performed considering different possible solutions: thermal switches, deployable panels, freezing-and-thawing heat pipes, phase change material connectors. Drastically simplified 1D analysis was extensively used to analyse temperatures and heat fluxes.
Afterwards feasibility study was done to select optimal with respect to market availability and manufacturability of the desired solutions.
