ATCS Operations during Columbus Mission: Flight Data Evaluation and Correlation

The Columbus water loop active thermal control system (ATCS) started its operations on early 2008 as main thermal bus for the internal equipments of the laboratory. From then on, several events occurred like internal payloads activations/deactivations, Condensing Heat eXchanger (CHX) dry-out, Intermediate Heat eXchangers (IHX) insertions, by-passes opening and so on. Even if the control system stability was beyond dispute, some of these events produced unexpected transients, posing some problems to the overall system operations. Scope of this paper is to provide a brief overview of the system alerts and describe the major events occurred, the use of mathematical modelling analysis and correlation for the engineering evaluations and finally the agreed actions applied in flight operations.