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The Automated Transfer Vehicle (ATV) Thermal Control System (TCS) has the task to ensure the required internal environment at level of pressurized module and to thermally control the not pressurised modules and installed equipment, using passive and active control means, in response to the relevant applicable requirements. The ATV vehicle is assially subdivided into three main modules: the Integrated Cargo Carrier (ICC), the Equipped Avionics Bay (EAB) and the Equipped Propulsion Bay (EPB). Each of these modules present elaborated and specific thermal design solutions, to satisfy the different required operative tasks. The extensive thermal analysis campaign performed at ATV vehicle level and in progress for the next Qualification Review (QR) to justify and support the thermal control design solutions and verification status is described.

The INTEGRAL (International Gamma Ray Astrophysics Laboratory) program is an ESA observatory scientific satellite to be used for gamma ray astronomy, while ARTEMIS (Advanced Data Relay and Technology Mission) is an ESA program to be used for data relay and technology demonstration. ARTEMIS was launched on the 12th of July 2001 with an Ariane V launcher from CSG, after successful completion of the System Environmental test campaign at ESTEC including Solar Simulation Thermal Balance tests on PFM (1998). INTEGRAL has been successfully launched on the 17th of October 2002 with a Proton launcher from Baikonour Cosmodrome, after completion of the System Environmental test campaign at ESTEC including Solar Simulation Thermal Balance tests on STM (1998) and PFM (2002).

The Columbus laboratory module for the International Space Station (ISS) uses active thermal control for cooling of avionics and payload in the pressurized compartment. The Active Thermal Control Subsystem (ATCS) is based on a water loop rejecting waste heat to the Medium Temperature Heat Exchanger and Low Temperature Heat Exchanger on Node 2, part of the US Segment of the ISS. Flow and temperature control in the ATCS is achieved by means of the Water Pump Assembly (WPA) and the 3-Way Modulating Valve (WTMO) units. For the flow control the WPA speed is commanded so that a fixed pressure drop is maintained over the plenum with the avionics and payload branches. Adjusting the WTMO internal flow split permit the two active units to perform the CHX and plenum inlet temperature control. The WPA includes a filter and an accumulator to control the pressure in the ATCS and to compensate for leakage and temperature-dependent volume variations.

European Space Agency's (ESA's) Columbus module was launched on February 7, 2008. This marks the completion of more than 10 years of development. It is a major step forward for Europe in the area of Environmental Control and Life Support (ECLS) as Columbus contains several major assemblies which have been developed in Europe. These include the Condensing Heat Exchanger, Condensate Water Separator and the Cabin Fans. The paper gives a short overview of the system and its features and it will report the experiences from the initial activation and operations phase.

ESA and NASA agencies agreed to run an interface compatibility test at the EADS facility between the Columbus flight module and a duplicate ground unit of a currently on-orbit US International Standard Payload Rack, the Human Research Facility (HRF) Flight Prototype Rack (FPR). The purpose of the test was to demonstrate the capability to run US payloads inside the European ISS module Columbus. One of the critical aspects to be verified to ensure suitable operations of the two systems was the combined performance of the hydraulic controls resident in the HRF and Columbus coolant loops. A hydraulic model of the HRF FPR was developed and combined with the Columbus Active Thermal Control System (ATCS) model. Several coupled thermal-hydraulic test cases were then performed, preceded by mathematical analysis, required to predict safe test conditions and to optimize the Columbus valve configurations.

During the last years extensive work has been done to design and develop the Closed-Loop Air Revitalization System ARES. The potential of ARES e.g. as part of the ISS ECLSS is to significantly reduce the water upload demand and to increase the safety of the crew by reducing dependence on re-supply flights. The design is adapted to the interfaces of the new base lined Russian MLM module as possible location for a future installation of ARES. Due to the lack of orbital support equipment and interfaces to a waste water bus, to a feed water supply line and due to the availability of only one single vent line it was necessary to make the ARES process water loop as independent as possible from the host vehicle. Another optimization effort was to match the CO2 desorption profile with the available hydrogen flow to achieve a sufficient water recovery performance, while meeting all related safety requirements, minimizing complexity and improving reliability.

1 The Closed-Loop Air REvitalisation System ARES is a proof of technology Payload. The objective of ARES is to demonstrate with regenerative processes: the provision of the capability for carbon dioxide removal from the module atmosphere, the return supply of breathable oxygen within a closed-loop process, the conversion of the hydrogen, resulting from the oxygen generation via electrolysis, to water. The ARES Payload is foreseen to be installed - in 2012 - onboard the ISS in the Columbus Module. The operation of ARES - in a representative manned microgravity environment - will produce valuable operational data on a system which is based on technologies which are different from other air revitalization systems presently in use. The ARES Technology Demonstrator Payload development started in 2003 with a Phase B, see references [1], [2], [3] and [4]. ARES is presently in Phase C1 and a PDR is scheduled for the beginning of 2009.

EADS SPACE Transportation GmbH designed, built and tested a condensate buffer to be located between a Condensing Heat Exchanger (CHX) and a Condensate Water Separator Assembly (CWSA), as part of the ECLSS of the European Columbus Module. Under zero-g conditions, the separation of water from an air-water mixture is always difficult, especially if a passive device is to be used such as the low power consuming Columbus CWSA. The additional buffer volume reduces condensate water peaks reaching the CWSA to a level that excludes an overloading of the CWSA and a release of free water droplets into the air return to the cabin. In the CHX/CWSA system this may only be necessary under worst case operational conditions and with a failure of the qualified hydrophilic coating of the CHX. The buffer design principle was confirmed via prior analyses and on-ground testing. The performance of such a condensate buffer under micro-g conditions was verified during parabolic flights.

ESARAD is an integrated suite of analysis tools for thermal radiative analysis. The suite provides modules for: • Geometry Definition; • Calculation of view factor, radiative exchange factor and solar, albedo and planet flux results; •Visualization of models in orbit with pre- and post-processing of radiative and thermal results; • Reporting of all aspects of the model; and • Generation of Input Files for Thermal Analysis tools. ESARAD is driven by a fully developed GUI, providing the user with a simple, intuitive windows, menus, forms interface to all its features. A modern, block structured language can also be used to run ESARAD. This gives the advanced user great power and flexibility to perform the most complex analyses. ESARAD was designed and developed between 1988 and 1991 to replace the VWHEAT software used by ESA at that time.

The INTEGRAL (International Gamma Ray Astrophysics Laboratory) program is an ESA observatory scientific satellite to be used for gamma ray astronomy, It was successfully launched on the 17th of October 2002 with a Proton launcher from Baikonour Cosmodrome and after a dedicated Commissioning Phase it was ready to start its scientific mission. After 2 years the first lifetime goal (nominal lifetime) was reached and it entered the extended lifetime (3 additional years) Alenia Spazio, who had the role of Prime Contractor, was fully responsible of the Thermal Control of the satellite. During 2.5 years the satellite was carefully monitored and the thermal control design mounted on it has been capable to meet all the thermal requirements, providing the optimal thermal environment.

Given the constraints of the current launchers, manned exploration beyond LEO implies long time missions, a high mass of metabolic consumables and consequently regenerative life support technologies developments. To validate their efficiency, as well as their reliability, these technologies need to be tested in the most analog conditions (i.e. isolation, limited spare part, …). A large number of these conditions are met in the new permanent French-Italian settlement called Concordia, currently being built in the Antarctic continent. Over the last 15 years, ESA developed regenerative life support technologies. Two of these technologies: a Grey Water Treatment Unit and a Black Water Treatment Unit are currently assembled at the size of 15 to 70 persons to fulfill the Concordia crew needs The first technology is a multi step filtration system and will recycle the shower, washing machine, dish washer and cleaning water.

Italsat F1 is a communication satellite sponsored by the Italian Space Agency and developed by Alenia Spazio. The spacecraft consists with a platform, which provides all the required services, and three payloads: a global beam package, a multibeam package for domestic communication services at 20/30 GHz, and an experimental propagation package at 40/50 GHz which embraces the European continent. Italsat F1 was sent off by an Ariane IV launcher from the Kourou Space Center in French Guyana on January 16th,1991, and it has been operating since February 1991. Having gone through a complete cycle of solstices and equinoxes, Italsat experienced the extreme environmental conditions at its beginning of life. The flight data collected throughout the first year of operational life enabled a review of the spacecraft thermal performances. This paper presents an overview of in-orbit observed temperatures.

The Visual Video Target Switching Unit (VVTSU) is the control unit dedicated to the Visual Video Target (VVT). The VVTSA, grouping VVTSU and VVT, is a “two-boxes assy”, externally located on ATV Front Cone, used to allow ATV monitoring by crewmembers inside the ISS Service Module, during the final approach up to 500 m from the docking port. Alenia Spazio is the responsible of VVTSA and in particular of the design, assembly and qualification of the VVSTU unit: an Engineering Model (for avionic tests), a Qualification Model and two Flight Units (+ 1 Spare) have been designed, assembled and verified in Torino and L’ Aquila Laboratories. The VVTSU is powered during the Rendezvous and it presents a high power dissipation, if compared with the reduced dimensions. The thermal control of this unit has been realized using passive means: a high conductive coupling with the fixation bracket, jointed with a radiator on the VVTSU top face.

The launch and activation of ESA's Columbus module in early 2008 marked the completion of more than 10 years of development. Since then the Columbus ECLS is operating, including its major European ECLSS assemblies such as Condensing Heat Exchanger (CHX), Condensate Water Separator, Cabin Fans and Sensors. The paper will report the experiences from the first year of operations in terms of events, failures and lessons learned. Examples of this is the description of some off-nominal situations (such as Condensate Removal and IMV Return Fan failure, and relevant troubleshooting), and the preparation to Columbus Reduced Condensation Mode, as requested by NASA in order to minimize the crew time needed to empty Condensate Water Tanks in US Lab.

The Fluid Science Laboratory (FSL) is an advanced multi-user facility for conducting fluid physics research in microgravity conditions. It will be installed in the Columbus module of the International Space Station (ISS) scheduled for launch in 2004. FSL is being developed by a European industrial team, led by ALENIA SPAZIO of Italy, and managed by the European Space Agency (ESA). The FSL Thermal Environment Control (TEC) establishes a defined thermal environment during the complete experiment duration to keep the experiment and the supporting subsystems within their thermal requirements. The TEC is further subdivided into three sections. The Air Cooling Section is based on the Avionics Air Assembly (AAA) which generates air streams inside the Facility to collect, by forced convection, the waste heat from the electronics belonging to the various Subsystems. The Secondary Water Loop (SWL) cooling Section provides the cooled water to the Experiment Container.

This paper describes recent advances in MPB's approach to spacecraft thermal control based on a passive thin-film smart radiator tile (SRT) that employs a variable heat-transfer/emitter structure. This can be applied to Al thermal radiators as a direct replacement for the existing OSR (optical second-reflector) radiator tiles with a net added mass under 100 gm/m2. The SRT employs a smart, integrated thin-film structure based on the nano-engineering of V1-x-yMxNyOn that facilitates thermal control by dynamically modifying the net infrared emittance passively in response to the temperature of the space structure. Dopants, M and N, are employed to tailor the transition temperature characteristics of the tuneable IR emittance. This facilitates thermal emissivities below 0.3 to dark space at lower temperatures that enhance the self-heating of the spacecraft to reduce heater requirements.