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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.

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.

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.

Because of the reduction on the remaining Shuttle launches, the initial mission that was assigned for MELFI, the Minus Eighty degrees Celsius Laboratory Freezer for ISS, has been significantly modified. While the design was made for a MELFI flying 15 times over a period of 10 years with individual missions no longer than 2 years, present scenario requires to have MELFI in orbit up to 7 years. Extending the MELFI on orbit life from two to seven years has required staggered assessments, each of them aiming at preserving as much as possible the existing design. The potential life limited items are evaluated. On orbit maintenance will be extended for a longer period and maintenance activities foreseen initially to be done on ground between flights will be adapted for orbit. Degraded modes are evaluated so that MELFI ensures its mission at the end of the life even with some off-nominal conditions.

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.

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.

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.

For experiments with plants and other organisms in microgravity, a facility with a life support and an observation system, both of them operating by remote control on a centrifuge rotor, is deemed necessary. This would enable the scientist on ground to study development and behavior of organisms under microgravity and different acceleration conditions in Space, also with the possibility of a permanent on-board 1-g control. ESA’s EMCS (European Modular Cultivation System) has been designed for these kinds of experiments, especially for long lasting plant cultivations from seed-to-seed. However, the experiment preparation, the design and testing of the experiment hardware and the ground reference need to be done in a ground model that accommodates all features of the flight model, but is adapted to the gravity conditions on ground. This model, called the ERM (Experiment Reference Model), was delivered to ESA in 2002 and has been submitted to extensive testing.

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.

Membrane gas absorption and desorption (MGA/MGD) for the removal of CO2 in manned spacecraft or other enclosed environment is subject of study by Stork and TNO for many years. The system is based on the combination of membrane separation and gas absorption. Advantage of this technology is that the system not only can be used to remove the carbon dioxide but also to control the relative humidity and temperature. Absorption of moisture and heat is achieved by cooling the absorption liquid below the dewpoint temperature of the gas stream. From the start in 1995, the Crew Transfer Vehicle is used as a basis for the design (1,2). Compared to the planned air conditioning system, consisting of a condensing heat exchanger, LiOH cartridges and a water evaporator assembly, MGA/MGD shows advantage in volume, mass and power consumption. The absorption liquid circulates through the spacecraft thermal control loop, replacing the coolant water.

This work concerns the model of a biological life support system consisting of higher plants, a unit of “biological combustion”, a physicochemical reactor, and 1/30 of a human. The cycling of the main biogenic elements of the system, water, and carbon dioxide was closed to a high degree (more than 95%). Experimental-theoretical analysis of the cycling processes in the system was based on the calculations of mass exchange rates dynamics and some stoichiometric equations. The model was designed for the study of mechanisms of material transformation and the directions of mass exchange processes in the artificial ecosystems.

EcosimPro‘s capability to solve a problem domain that can be represented by Differential-Algebraic Equations (DAE) and discrete events, make it particularly attractive to model bio-regenerative life support systems. Components of the envisaged MELiSSA bio-regenerative life support system are driven by the adaptation of the biomass to changing environmental conditions, which could be of continuous nature, such as depletion or replenishment of nutrition, and discrete events, such as step changes in light fluxes and control interactions. The authors first present simulation results for a closed and an open loop bio-regenerative system. The simulations include the establishment of a quasi-steady state, reaction to step changes including a mass balance check, and the simulation of a controlled bioreactor. The results demonstrate the capability of this tool to model components of a bio-regenerative life support system, as well as an entire bio-regenerative life support system in the future.

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.

Temperature and humidity control are vital functions of an environmental control and life support system in a manned spacecraft. A MCHX Technology Demonstrator has been developed using hollow fiber membranes to remove heat and water vapor from the cabin air. The functional principle of the MCHX is based on micro porous hydrophobic hollow fiber membranes. Heat and water vapor are transferred through the membrane to the cooling the water. The water vapor will condense at the cooling water side. The technique promises a good alternative for the conventional noisy and power-consuming rotary condensate separator. This paper describes the MCHX development work including the rational for its concept, the module design and its performance data as a result of numerical predictions and a test campaign. The MCHX performance requirements are linked to those of the Columbus Laboratory, the European contribution to the International Space Station (ISS).