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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.

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.

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.

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.

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.

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).

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.

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 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.