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Viewing 1 to 30 of 38
2004-07-19
Technical Paper
2004-01-2398
Alexander Rodriguez, Ricardo Patrício, Johan Steelant, José Antonio Romera Perez
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.
2004-07-19
Technical Paper
2004-01-2565
A. Denaro, H. Ritter
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.
2009-07-12
Technical Paper
2009-01-2375
Sylvain Vey, Silvio Dolce, Elena Checa, Giovanni Macelloni
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.
2009-07-12
Technical Paper
2009-01-2573
Alberto Franzoso, Marco Molina, Francisco Romera Fernandez, Guido Barbagallo
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.
2009-07-12
Technical Paper
2009-01-2558
Jean-Christophe Guyot, Patrick Oger, Pascal Vincent, Bachisio Dore, Frank Bouckaert
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.
2009-07-12
Technical Paper
2009-01-2556
Pascal Vincent, Jean-Christophe Guyot, Patrick Oger, Frank Bouckaert
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.
2005-07-11
Technical Paper
2005-01-2841
Knut R. Fossum, Ann-Iren Kittang, Tor-Henning Iversen, Enno Brinckmann, Peter Schiller
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.
2005-07-11
Technical Paper
2005-01-2902
M.P. Heß, J. Winter, B. Hummelsberger, P. di Palermo
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.
2007-07-09
Technical Paper
2007-01-3030
Z. Szigetvari, B. Schmitz, J. Witt, J. Persson, P. Vaccaneo, P. Artusio
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.
2007-07-09
Technical Paper
2007-01-3029
Jean Cheganças, Jérôme Guichard, Lina De Parolis
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.
2008-06-29
Technical Paper
2008-01-2033
Z. Szigetvari, J. Witt, J. Persson, P. Vaccaneo
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.
2005-07-11
Technical Paper
2005-01-3117
Z. Szigetvari, J. Witt, J. Persson, B. Lehmann, E. H. Turner, P. Vaccaneo, S. Hinderer
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.
1992-07-01
Technical Paper
921292
R. Pérez, V. Torroglosa, A. Lebru, M. Novara
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).
1994-06-01
Technical Paper
941572
S. Dolce, G. Spinella, P. Pieper, C. Lusteau
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.
1992-08-03
Technical Paper
929243
Douglas Alexander, Ted Edge, Douglas Willowby, Lothar Gerlach
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.
1993-07-01
Technical Paper
932126
Ch. Lasseur, C. Tamponnet, C. Savage
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.
1993-07-01
Technical Paper
932101
U. Rieck, W. Fischer, G. Kleen, D. Müller-Wiesner, K. H. Stecher, J. Walter, J. Witt, L. Fanchi
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.
1999-06-22
Technical Paper
1999-01-2366
Réjean J. L. Grard
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.
2000-07-10
Technical Paper
2000-01-2307
C. Damasio, B. Miedza, J.P. Guerin, P. Oger, J.A. Romera Perez
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.
2000-07-10
Technical Paper
2000-01-2302
Atle Honne, Ib-Rune Johansen, Timo Stuffler, Herbert Mosebach, Dirk Kampf, Hermann Abele, Gijsbert Tan
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]).
2000-07-10
Technical Paper
2000-01-2496
Jan Doornink, John Kanis, Eduard van den Heuvel, Giovanni Colangelo
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.
2000-07-10
Technical Paper
2000-01-2472
Enno Brinckmann, Claude Brillouet
Two ESA facilities will be available for plant research and other biological experiments on the International Space Station: the European Modular Cultivation System (EMCS) in the US “Destiny” Module and BIOLAB in the European “Columbus” Laboratory. Both facilities use standard experiment containers, mounted on centrifuges and connected to life support systems, allowing telescience-controlled acceleration studies (0.001×g up to 2.0×g) and continuation of microgravity research on protoplasts, callus cultures, algae, fungi and seedlings, as earlier flown on Biorack, and new experiments with larger specimens of fungi, mosses and vascular plants.
2003-07-07
Technical Paper
2003-01-2466
P. Oger, J-P. Hulier, J. A. Romera Perez
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.
2003-07-07
Technical Paper
2003-01-2417
J.-B. Gros, A. A. Tikhomirov, S. A. Ushakova, N.S. Manukovsky, V.G. Gubanov, Yu.V. Barkhatov, I.G. Zolotukhin, V.S. Kovalev, Ch. Lasseur
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.
2003-07-07
Technical Paper
2003-01-2410
A. Rodriguez, L. Ordonez Inda, L. Poughon
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.
2003-07-07
Technical Paper
2003-01-2348
C. van Driel, F. Eckhard, P. H. M. Feron, A. Rodriguez, G. B. Tan
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.
2005-07-11
Technical Paper
2005-01-2796
Alexander Rodriguez, Jan Persson, Johannes Witt, Paolo Vaccaneo
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.
1992-07-01
Technical Paper
921326
P. Braund, C. Lusteau, B. Pieper
The ESA Polar Platform, as part of the ESA Columbus Development Programme, is scheduled to be launched as single passenger by an Ariane 5 vehicle in mid 1998. The multimission platform is designed to accommodate a wide range of payload complements to be flown on a series of missions in order to satisfy the growing future earth observation needs in continuation of the current ERS programme. Multi-mission capability is achieved by design modularity wherever feasible and cost-effective. This paper describes the thermal control design of the Polar Platform which follows its modular configuration and which has to cope with a wide range of generic performance parameters, whilst being adaptable to provide optimised performance for specific missions. Special thermal control features are highlighted as the software and hardware controlled heater systems, thermal doublers using carbon / carbon material and the battery compartment heat pipe radiator.
2003-07-07
Technical Paper
2003-01-2628
Jobst Hapke, Chakkrit Na Ranong, Karlheinz Brodt, Gijsbert Tan
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).
2000-07-10
Technical Paper
2000-01-2353
C. van Driel, F. Eckhard, P. H. M. Feron, C. J. Savage
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.
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