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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.

Methane-filled heat pipes have been developed and qualified for the SCIAMACHY thermal bus assembly. The heat pipes provide an efficient heat transfer in the temperature range 100-160 K. Extensive qualification testing has been performed. The thermal bus assembly is part of the Thermal Bus Unit (TBU) of the SCIAMACHY Radiant Cooler.

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.

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.

Jules Verne (JV) is the name of the first Automated Transfer Vehicle (ATV) developed by ASTRIUM Space Transportation on behalf of European Space Agency (ESA). JV was launched the 9 March 2008 by ARIANE 5 and performed the 3 April 2008 its automatic rendezvous and docking to the International Space Station (ISS) to which it remained attached up to the 5 September 2008. In the meantime, JV has provided the ISS with dry and fluid cargo and performed one refueling, four ISS re-boosts and one Debris Avoidance Maneuver. JV completed its successful mission by offloading waste and was destroyed during its re-entry the 29 September 2008. Generally, development and verification of Power management rely on classical thermal and electrical engineering.

Jules Verne – the first ATV model developed by ASTRIUM on behalf of ESA – has been controlled by CNES Toulouse Control Centre from March to September 2008. The Engineering Support Team (EST) was in charge to provide System expertise and to propose relevant recommendations in case of off nominal situations. This paper deals with the operations carried out by the EST Thermal position during the JV flight, such as: Identification of thermal anomalies triggered by onboard software or by ground monitoring; Analysis of actual situation from available flight data; Correction implemented thanks to a complete set of commands and procedures; Check on the on-board configuration after correction uploading.

The MELISSA (Microbial Ecological LIfe Support System Alternative) project has been set up to be a model for the studies on ecological life support systems for long term space missions. The compartmentalisation of the loop, the choice of the micro-organisms and the axenic conditions have been selected in order to simplify the behaviour of this artificial ecosystem and allow a deterministic and engineering approach. In this framework the MELISSA project has now been running since beginning 1989. In this paper we present the general approach of the study, the scientific results obtained on each independent compartment (mass balance, growth kinetics, limitations, compound conversions,..), the tests of toxicity already performed between some compartments and their effect on the growth kinetics. The technical results on instrumentation and control aspects, and the current status of the ESA/ESTEC hardware are also reviewed.

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.

For a planetary base, a reliable life support system including food and water supply, gas generation and waste management is a condition sine qua non. While for a short-term period the life support system may be an open loop, i.e. water, gases and food provided from the Earth, for long-term missions the system has to become more and more regenerative. Advanced life support systems with biological regenerative processes have been studied for many years and the processes within the different compartments are rather complete and known to a certain extent. The knowledge of the associated interfaces, the management of the input and output phases: liquid, solid, gas, between compartments, has been limited. Nowadays, it is well accepted that the management of these phases induces generic problems like capture, separation, transfer, mixing, and buffering. A first ESA study on these subjects started mid 2003.

EADS SPACE Transportation has developed and qualified under ESA contract the Refrigerator/Freezer Rack (RFR) for use by NASA on-board the ISS. This paper will present a general overview of the RFR system design, the qualification test results and an outlook to potential future usage of the RFR.

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.

Reusability of next generation launchers needs that cryogenic insulation of LH2 and LOX tanks is able to withstand without significant degradation critical environments experienced especially during pre-launch and re-entry phases. An extensive characterisation campaign is presently on-going to improve performances of available insulations that only partially sustain thermo-mechanical loads and physico-chemical characteristics of the operative environment. The campaign is divided in two different slices: The first one has the objective of outlining the best insulation material and configuration; the second one foresses a test representative of the flight conditions performed with the selected insulation on a sub-scale Al-Li tank demonstrator. Preliminary results achieved in the frame of the first slice are presented.

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.

If man leaves Earth for a long time to settlements on the Moon or Mars, he will be dependent of Closed Ecological Life Support Systems (CELSS) for the recycling of waste and the production of food. A large amount of the inedible plant material has to be pretreated and converted into a form which can be recycled. The main portion of this biomass is lignocellulosic material which cannot or only slightly be degraded by micro-organisms. White-rot fungi like Pleurotus spp. (oyster mushroom) or Lentinus edodes (shiitake or black Chinese mushroom) degrade these fibrous material more efficient than other micro-organisms and produce edible and also tasteful mushrooms which will increase the quality and nutritional value of the settlers diet. In the MELISSA (Micro-Ecological Life Support Alternative) project, a project under the management of ESA to study CELLS, it was observed that also human faeces contain a considerable amount of fibrous materials which pile in the loop.

Membrane gas absorption for the control of CO2 in manned spacecrafts is studied by Stork and TNO. Membrane Gas Absorption (MGA) is based on the combination of membrane separation and gas absorption. The cabin air of a spacecraft is fed along one side of a hydrophobic membrane. The air diffuses through the membrane and the CO2 is selectively absorbed by an absorption liquid. Experiments showed that the MGA system can not only be used for the removal of the carbon dioxide but also can be applied to control the relative humidity and temperature of the cabin atmosphere. Absorption of moisture and heat is achieved by cooling the absorption liquid below the dewpoint temperature of the gas stream. This paper deals with the design aspects of a MGA system for combined CO2, humidity and thermal control aboard the Crew Transfer Vehicle. Furthermore, design data are presented for a similar system aboard the International Space Station.

The Minus Eighty (Degrees Celsius) Laboratory Freezer for the International Space Station (MELFI) is one of the freezers developed by ESA on behalf of NASA. Peculiar requirements for that facility are the long-term storage at low temperature, the rapid freezing of specimen to the required temperature, the large cold volume (300 l) and the low power consumption. To verify those requirements before the manufacturing of the flight hardware, a dedicated test campaign was performed on a ground model. This paper will start with a system overview, showing the main features of MELFI. The test set-up as well as their results will be presented and discussed, with particular emphasis on the methods used to predict the on-orbit (0-gravity) behaviour, by avoiding the sample internal convection and dewar internal convection during the test execution.

This paper presents the status of ongoing BB studies for an optimized trace gas monitoring (TGM) system configured to simultaneously and quasi-online detect (quantitatively and qualitatively) 30 different trace gases in manned spacecraft. The system principle relies on the detection of molecule absorption lines in the infrared being converted into a measured spectrum by a Fourier Transform Infrared (FTIR) Spectrometer. The work is based on 10 years study phases aiming now towards performance demonstration on unknown gas mixtures and an in-flight demonstration on Space Shuttle or ISS. The theoretical background, sensor combinations, SW principle descriptions and multi-module monitoring strategies have been reported earlier (please refer to reference [1] - [4], [6]).