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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.

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.

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.

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.

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.

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.

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]).

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.

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.

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.

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.

The electric current which circulates downwards in the Earth atmosphere results from the motion of positive and negative ions drifting in opposite directions under the influence of an electric field. A body such as a balloon or a gondola, moving upwards against the electric field collects an excess of positive ions, whereas a falling body, such as a water drop, may acquire a negative charge. In a similar way, parcels of hot and cold air ascending or descending in a cloud are selectively charged. This model is proposed as an explanation for the charge separation mechanism which takes place within thunderstorm clouds characterized by vigourous turbulence and convection.

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 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.

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.

ECOSIM is a software tool for the simulation of Environmental Control and Life Support (ECLS) systems which has been developed for the European Space Agency. A preliminary model of the Hermes Air Management System has been developed during the ECOSIM testing in order to assess the functionality of the software and to verify its results with those obtained from previous simulation tools. The model represents the Hermes cabin with its crew and it includes submodels for the sub-systems performing the following functions: Temperature and Humidity Control. Total Pressure and Composition Control. Air revitalisation. The interactions between these different subsystem are taken into account by the model, while many of the previous simulations made assumptions to decouple the different subsystems (e.g: a constant cabin temperature has been assumed during cabin depressurization transients, to decouple the pressure control section from the air conditioning section).

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.

The Hubble space telescope (HST) solar array consists of two identical double roll-out wings designed after the Hughes flexible roll-up solar array (FRUSA) and was developed by the European Space Agency (ESA) to meet specified HST power output requirements at the end of 2 years, with a functional lifetime of 5 years. The requirement that the HST solar array remain functional both mechanically and electrically during its 5-year lifetime meant that the array must withstand 30,000 low-Earth orbit (LEO) thermal cycles between approximately +100 and -100 °C. In order to evaluate the ability of the array to meet this requirement, an accelerated thermal cycle test in vacuum was conducted at NASA's Marshall Space Flight Center (MSFC), using two 128-cell solar array modules which duplicated the flight HST solar array. Several other tests were performed on the modules.