Speaker
Description
Atmospheric Remote-sensing Infrared Exoplanet Large-survey (Ariel) is the fourth medium-sized mission (M4) selected in the context of ESA's Cosmic Vision 2015-2025 programme and is scheduled for launch in 2029. Thermal control of the payload is based on a passive and active cooling approach. Passive cooling is achieved by a V-Groove shield system that takes advantage of the favourable thermal conditions of the L2 orbit to cool the telescope and the optical bench to stable temperatures <60 K. One instrument requires to operate below 42 K, which is achieved by an active cooling system based on a Neon Joule-Thomson cold end. To ensure the proper functionality of the mirrors, detectors and other optical equipment at operating temperature, an in-flight decontamination process will be performed to remove any thin ice films deposited on the critical optical surfaces of other surrounding elements. This study presents the preliminary results of the thermal study carried out to size the Ariel decontamination lines on ESATAN-TMS. Two scenarios have been considered, the first one, during the cool-down on the journey to L2, and the second one, a possible case of having to heat from cold (~60 K). In addition, since this type of analysis requires a considerable simulation time, the results in terms of heater duty cycle have been compared with the simulation time step, obtaining a trade-off between computational cost and accuracy.
