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In-Orbit Experience with Sciamachy Active Thermal Control Systems
ISSN: 0148-7191, e-ISSN: 2688-3627
Published July 07, 2003 by SAE International in United States
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Sciamachy is a Dutch/German Earth Observation Instrument on board of the European Envisat satellite, which was launched on March 1st 2002. The goal of the instrument is to observe concentrations of multiple trace gases in the upper atmosphere. Due to the character of the instrument special thermal control methods have been incorporated in the instrument design. Amongst these are the active thermal control loops for the detector modules and the optical bench module. The 8 detector modules, which are cooled with a passive cooler to circa 150 - 240 K, are stabilized with three heaters that are controlled via telemetry. The optical bench module is provided with three feedback-controlled heater loops. This paper focusses on the in-orbit thermal observations, the correlation with the thermal predictions, the fine-tuning of the parameters in the active thermal control systems, and the important role of the thermal control heater system in the solution of problems with outgassing-induced ice layers on the coldest detectors.
The temperature result of channels 1-6 shows very good comparison with the predictions. The temperature level and stability is within requirements. The trimheater power available seems enough to keep the temperatures stable throughout its lifetime. More definite conclusions can be made after one whole season, when degradation results are possible to deduct more accurately. The result until now however indicate a first year degradation < 1 K.
The predicted sensitivities, with one correction, correlate well with the observed temperature changes.
The temperatures of channels 7 & 8 are able to stay below the required 150 K limit. However a clear contamination effect from within the detector module still can be observed. After a number of decontamination loops it is clear that improvements are made.
CitationLemmen, M., Koorevaar, F., and Pennings, N., "In-Orbit Experience with Sciamachy Active Thermal Control Systems," SAE Technical Paper 2003-01-2470, 2003, https://doi.org/10.4271/2003-01-2470.
- Reijneker P. Deutz A. Sciamachy optical assembly thermal design 24 th ICES and 5th European Symposium on Space Environmental Control Systems Friedrichshafen, Germany June 20-23 1994
- Wigbers I. The Design Development and Qualification of the Sciamachy Radiant Cooler 9 th Cryocooler Conference Waterville Valley New Hampshire, USA June 25-27 1996
- Coesel Rinus Cruijssen Henk Wigbers Ino “The development of the Sciamachy Radiant Cooler” 6th European Symposium on Space Environmental Control Systems 1 169 173 Noordwijk, The Netherlands 20-22 May 1997
- Lemmen M.H.J. Coesel M.J.N. “Thermal balance test results of Sciamachy Thermal Bus Unit” 6th European Symposium on Space Environmental Control Systems 1 233 237 Noordwijk, The Netherlands 20-22 May 1997
- Active Thermal Control System of the Sciamachy Optical assembly Boslooper E.C. Kouwen J. Barbosa H. Fokker Space, Leiden Proceedings of the 6 th European Symposium on Space Environmental Control Systems Noordwijk 20-22 may 1997 August 1997
- Thermal qualification of the Sciamachy passive cryogenic cooler Lemmen M.H.J. Boslooper E.C. Coesel M.J.N. International Conference on Environmental Systems SAE Denver, CO, USA July 1999
- Sciamachy Ready for Launch Kamp A. Fokker Space, Leiden Dobber M. TNO-TPD, Delft, R. van der Linden, SRON, Utrecht, Acta Astronautica 47 2-9 289 296 2000
- Optimization of thermal control systems during Sciamachy commissioning phase Pennings N.H. Dutch Space, Leiden 32nd International Conference on Environmental Systems (ICES) San Antonio, TX, USA July 2002