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In a harmonized ESA/NIVR project the performance of membrane gas absorption for the simultaneous removal of carbon dioxide and moisture has been determined experimentally at carbon dioxide and humidity concentration levels representative for spacecraft conditions. Performance data at several experimental conditions have been collected. Removal of moisture can be controlled by the temperature of the absorption liquid. Removal of carbon dioxide is slightly affected by the temperature of the absorption liquid. Based on these measurements a conceptual design for a carbon dioxide and humidity control system for the Crew Transport Vehicle (CTV) is made. For the regeneration step in this design a number of assumptions have been made. The multifunctionality of membrane gas absorption makes it possible to combine a number of functions in one compact system.

Columbus has been delivered to Kennedy Space Center (KSC) in summer 2006 for final integration, test and mission preparation. In the frame of these “last” phase activities also the Active Thermal Control System (ATCS) had to be finalized and prepared for the launch resp. mission. Due to unexpected late failures resp. malfunctions detected on component/unit level of the ATCS, refurbishment, integration / exchange of the relevant components and re-testing of their system level functions had to be done. Moreover, the still outstanding system level fluid leakage test of the ATCS had to be revised and completed. In addition to the required late refurbishment, integration and test activities, in certain cases also operational workarounds had to be evaluated. They should help to cope with similar contingency situations during operation of the ATCS on-orbit.

An advanced trace gas monitoring system for long duration manned space missions - such as the International Space Station - is discussed. The system proposed is a combination of a Fourier-Transform Infrared Spectrometer (FTIR) and a distributed ‘Smart Gas Sensor system (SGS). In a running multi-phase programme [1,2] the FTIR technology, applying novel analysis methods, has been demonstrated to handle multi-component gas measurements, including identification and quantification of 20 important trace gases in a mixture. In the current phase 3, initiated end of 1997, a fully operational FTIR technology demonstration model will be manufactured and tested. The SGS consists of an array of twenty electrically conductive polymer sensors supplemented with an array of quartz crystal microbalance sensors. The technology has been tested on the Russian MIR space station and is currently miniaturized into a second-generation flight model.

Final preparation and configuration of the Columbus module at the Kennedy Space Center (KSC) required the performance of system level tests with the Active Thermal Control System (ATCS). These tests represented the very last system level activities having been concluded on the Columbus module before handover to NASA for space shuttle integration. Those very last tests, performed with the ATCS comprised the final ATCS Leakage Test, the final calibration and adjustment of the Water Flow Selection Valves (WFSV) and Water On/Off Valves (WOOV) as well as a sophisticated ATCS Residual Air Removal test. The above listed tests have been successfully performed and test data evaluated for verification closeout as well as input delivery for operational Flight Rules and Procedures. Some of the above mentioned tests have been performed the first time hence, a succeeding lessons learned collection followed in order to improve the perspectives of future tests.

After several years of development the first European Automated Transfer Vehicle (ATV) developed by ESA called Jules Verne completed successfully its seven-month ISS logistics mission. Launched the 9 March 2008 on an Ariane 5 launcher, the ATV performed the 3 April 2008 its rendezvous and docking to the International Space Station to which it remained attached for five months. This paper presents in a first part the ATV thermal control architecture based on a innovative active thermal control design built around 40 Variable Conductance Heat Pipes (VCHP) controlling the heat rejection and in a second part the in-flight thermal control behavior of the ATV Jules Verne observed during the seven months mission in both free flight and attached to ISS phases.

In recent years there is growing interest, on the part of the remote sensing community, in using the Antarctic area, for calibrating and validating data of satellite-borne microwave radiometers. With a view to the launching of the ESA's SMOS satellite, which is a satellite designed to observe soil moisture over the Earth landmasses, salinity over the oceans and to provide observations over regions of ice and snow, an experimental activity called DOMEX was started at Dome-C Antarctica. The main scientific objectives of this activity are to provide microwave data for SMOS satellite calibration and in particular: the continuous acquisition of a calibrated time-series of microwave and thermal Infrared (8-14micron) emission over an entire Austral annual cycle, the acquisition of a long time-series of snow measurements and the acquisition of relevant local atmospheric measurements from the local weather station. This paper is focusing on the thermal design, analysis and testing of Domex-2.

A Heat Switch has been developed, namely a device able to autonomously regulate its own thermal conductance in function of the equipment dissipation and environmental heat sink conditions. It is based on a Loop Heat Pipe (LHP) technology, with a passive bypass valve which diverts the flow to the Compensation Chamber when needed for regulation purposes. The target application is the potential use on a Mars Rover thermal control system. The paper recalls the Heat Switch design, and reports the results of an extensive test campaign on the ground demonstrator. The performance of the device was found extremely satisfying, and often exceeded the system requirements.

The Automated Transfer Vehicle will provide ISS with reboost, attitude control functions, with water, gas and propellant and with dry cargo. It is a 20 tons expendable vehicle launched by Ariane. It performs a rendezvous and docking with the Russian Segment. It remains attached up to 6 months before a destructive reentry. During PDR campaign, it was decided to change the ATV Thermal Control System from semi-passive (see reference 1) to active system to comply with electrical power budget and get the ATV power autonomy. This system is based on 40 Variable Conductance Heat Pipes controlling the heat rejection of the avionics items toward space. This paper presents the new thermal control system of the ATV and its verification and qualification logic.

During Extravehicular Activities (EVA) an astronaut has to be protected against various external factors ranging from mechanical hazards to solar radiation and micrometeoroids. An important element in this external protection is the outermost fabric layer. It has to ensure the mechanical protection of the pressure retention bladder and at the same time - by its thermooptical properties - plays an important role in the thermal control of the space suit. New weaving and knitting technologies enable the fabrication of so-called 3-D fabrics with interconnected layers and local variation of properties in one manufacturing step. By this a tailored design of protection properties is possible. A study has been performed to define concepts adapted for use on a European Space Suit. Different fabric samples were manufactured and tested, amongst others, for strength, flexibility, puncture and wear resistance, UV stability, flammability, out/offgassing and micrometeoroid protection effctiveness.

The European Polar Platform is a remote sensing satellite with the primary objective, in the ENVISAT-1 P/L configuration, to monitor and study the earth and its environment. The platform thermal design is passive assisted by heaters. Externally mounted P/Ls are responsible for their-own thermal control and are required to be thermally decoupled from the platform. The P/L thermal design is largely dependent on their detectors required temperature and stability. A wide range of design solutions is found: Stirling cycle coolers, Peltier elements, passive radiant coolers, heat pipe radiators. This paper describes the overall thermal design of the platform and the P/Ls, the principles of the selected ENVISAT-1 P/L accommodation, the relevant P/L to platform I/F design solutions and outlines the platform and P/Ls thermal verification logic.

The cabin space of the Columbus APM is well ventilated by air entering through multiple air diffusers and exiting via the return grid and hatch. Therefore, the heat transfers by bulk fluid motion and by convection to the walls need to be experimentally and/or numerically investigated and implemented in the thermal mathematical models (TMM) describing the cabin. CFD analysis provided key data on the thermal couplings due to convective heat transfer and bulk fluid motion for the thermal mathematical model, which in turn was used to correlate test data from an environmental control system test and to provide supplemental information on assumptions used in the lumped capacitance model. This paper presents the logic and results of the steady-state CFD analysis, the potential implementation of the results in a thermal mathematical model, and compares these results with test data obtained during a separate Columbus cabin ventilation qualification test.

Verification of the Integrated Overall Thermal Mathematical Model (IOTMM) is one of the last tasks in the thermal and environmental control area of the Columbus module. For this purpose a specific test covering as well thermal-hydraulic performance tests as Environmental Control and Life Support (ECLS) cabin temperature control functions has been defined and performed on the european Columbus Protoflight Model (PFM) in Bremen in 2003. This Environmental Control System test was successful for all Active Thermal Control System (ATCS) related thermal-hydraulic functions and could provide sufficient data for a proper IOTMM correlation. However, it failed to verify the ECLS related functions as cabin temperature control and ventilation. Data, which have been generated during this first test, could not be used for a successful IOTMM correlation related to ECLS subsystem performance and modelling.

Lumped parameter models are extensively used to calculate the thermal state of structures in a defined environment. Such models rely on the correct estimation of thermal couplings between the thermal nodes. Frequently, such conductances are difficult to establish using standard methods or given correlations. This paper presents methods to determine linear bulk flow conductances and linear conductances due to conduction and convection using computational fluid dynamics (CFD). The methods take advantage of grids of finite elements or finite volumes to model the structure, and the solution of the Navier-Stokes equations using CFD. Conductances due to conduction are determined in two ways. First, the conductance is calculated by means of geometric and material property analysis. Second, a thermal case was applied to compute the conductance. The results were compared subsequently. Fluid and convective conductances were calculated applying thermal and fluid dynamics cases.

The Automated Transfer Vehicle (ATV) is a European Space Agency (ESA) servicing and logistics transportation system for the periodic re-supply of the International Space Station (ISS). The ATV will be launched by Ariane 5 and will provide the following services to the ISS: refuelling of the ISS (transfer of fuel from ATV to the station), reboost of the ISS (increasing the station’s orbit altitude, using the ATV’s propulsion system), delivery of cargo such as compressed air, water and pressurised payloads to the station, destruction of waste from the station. The ATV is composed of the so-called Spacecraft (SC) and an Integrated Cargo Carrier (ICC). The Spacecraft includes the propulsion, reboost and attitude control systems, the avionics and the solar generator system.

As part of the European contribution to the Russian segment of the International Space Station (ISS), the European Robotic Arm (ERA) is designed under contract of the European Space Agency by Fokker Space as the Prime contractor. The particularly challenging aspect of the ERA thermal design is to enable ERA operation under all possible in-orbit thermal environmental conditions which are to be experienced throughout its 10 year life. These conditions can be between extreme cold without sunlight for hibernation to extreme hot with ERA operating in full sunlight in close vicinity to a large station item, for instance, the solar arrays. First a short description of the ERA system is given with a summary of the main thermal design features. The system level thermal balance test on the ERA Engineering Qualification Model (EQM) is intended to validate the system level thermal model, which consists of the subsystem thermal models as supplied by the respective subcontractors.