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Technical Paper

Extension to SINDA / FLUINT and ESATAN / FHTS for Transient Simulation of Air-Vapour in Pressurised Modules

2000-07-10
2000-01-2521
Thermo-hydraulic mathematical models of manned modules of the International Space Station [ISS] require to simulate also air-vapour flow in Environmental Control Systems [ECS] circuits. Although this can be obtained with available S/W, a complementary solution was developed, in order to overcome some S/W limitations and to ease exchange of models. It consists of a set of FORTRAN subroutines, that can be added to ESATAN/FHTS and SINDA/FLUINT thermo-hydraulic models for dry air, and simulate the effect of vapour in the airflow.
Technical Paper

1500 W Deployable Radiator with Loop Heat Pipe

2001-07-09
2001-01-2194
Two-phase capillary loops are being extensively studied as heat collection and rejection systems for space applications as they appear to satisfy several requirements like low weight, low volume, temperature control under variable heat loads and/or heat sink, operation under on ground and micro gravity conditions, simplicity of mounting and heat transfer through tortuous paths. In 1998–2000 Alenia defined and Lavochkin Association developed the Deployable Radiator on the base of honeycomb panels, axial grooved heat pipes and Loop Heat Pipe. It was designed for on-ground testing.
Technical Paper

The Effects of a Reduced Pressure Scenario on the Columbus APM Environmental Control System

1992-07-01
921247
Manned Space Systems are usually designed to support the crew atmospheric conditions equivalent to those at sea level. In phases with frequent Extra Vehicular Activities (EVA), a reduced pressure environment is preferable to facilitate the EVA suit prebreathing procedures. The Columbus Attached Pressurised Module (APM) will face both pressure scenarios during its life. Operation at different pressure levels primarily affects the performance of the Environmental Control System (ECS) of the pressurised elements. A lower air density results in reduced heat exchange, adversely affecting both the crew comfort and the electronics air cooling. This paper reports the results of a study performed to identify the constraints and the numerous potential problem areas related to APM operations at reduced pressure. Effects of the reduced pressure on the environmental parameters have been investigated.
Technical Paper

System Integration and Verification Approach for the Environmental Control System of the Columbus Attached Pressurised Module

1992-07-01
921261
The Attached Pressurised Module (APM) is the European element of the NASA Space Station Freedom (SSF). The environmental control of the APM is obtained through the combined effort of the Water Loops of the Thermal Control Subsystem (TCS) and the Cabin and Avionics Loops of the Environmental Control and Life Support Subsystem (ECLSS). Although the specific functions of ECLSS and TCS are separately verified at subsystem (S/S) level, their overall qualification is completed only after having carried out the functional and performance verification of the integrated Environmental Control System (ECS) inside the APM. To this purpose too, an APM Engineering Model (EM) development has been included in the programme. The Engineering Model is the element prototype, fully representative of the APM Flight Model (FM) but for the quality of the EEE components, as they are requested to be MIL-grade but not Hi-Rel.
Technical Paper

Columbus APM Water Loop Architecture Tradeoffs to Meet Space Station Freedom Interface Requirements

1992-07-01
921244
The Columbus Attached Pressurised Module (APM) Active Thermal Control System (ATCS) water loop collects the APM waste heat and transfers it to the Space Station Freedom (SSF) Central Thermal Bus (CTB). The interface between the APM water loop and the SSF ammonia loops is achieved with two ammonia/water interloop heat exchangers (IH/X), one being low temperature (LT) and the other moderate temperature (MT). The APM internal water loop provides cooling to payload and subsystem users which have varying temperature requirements at their heat rejection interfaces, and can be categorized as cold branch and warm branch users, (e.g. condensing heat exchanger (CHX) and refrigerator are cold branch users, while Avionic heat exchanger (AHX) and furnace payloads would be warm branch users.)
Technical Paper

Design Concepts for the Thermal Control of a Crew Transport Vehicle

1996-07-01
961542
Under the guidelines established by the European Space Agency (ESA), a specific effort was devoted to define the preliminary design concepts for a Crew Transport Vehicle (CTV) compatible with the Ariane 5 launcher. The mission objectives of this vehicle include the possibility of transporting 4 people (and a limited amount of pressurized payload) to the International Space Station Alpha (ISSA), and returning them to Earth safely. Different options were identified at system level, however a modular vehicle was commonly adopted: a Crew Module (CM) designed to withstand the typical phases of the atmospheric re-entry and provide an adequate environment for the crew during all the mission a Resource Module (RM) envisaged to provide the propulsion provisions for orbital transfer and deorbiting; in addition it carries all the necessary resources to support the mission from lift-off until separation from the CM.
Technical Paper

Thermal Comfort in the Columbus Attached Pressurized Module

1996-07-01
961367
The Columbus Attached Pressurised Module (APM) is intended to support a shirt-sleeve environment for crew activities. Top level requirements therefore define a cabin air temperature and humidity range (the so-called “Comfort Box”), extreme air velocities for ventilation in the centra aisle, maximum mean radiant temperature of the cabin walls. Air temperature selectability has to be ensured with adequate accuracy across the whole range. The APM environmental control system, in particular the Temperature and Humidity Control (THC) system, is designed and verified against these parameters. Cabin thermal conditions can be evaluated by the APM Integrated Overall Thermal Mathematical Model (IOTMM), representing the general thermal behaviour of the APM, including the THC system. Heat loads due to APM subsystem equipment and payloads, solar flux and the crew itself have been considered in the analyses.
Technical Paper

CFD Modelling on Fire Detection and Suppression in a Columbus Rack

1994-06-01
941607
The Columbus fire suppression procedure is based on a centralized CO2 distribution system which injects the CO2 stored in a tank into the volume where the fire has to be extinguished. The fire is detected in each volume by means of the so-called REP (Rack Essential Package), which contains a fan and the smoke sensor. In order to assess the Fire Detection and Suppression design concept and to identify possible critical areas, Alenia Spazio - with the support of Flowsolve UK, and on behalf of EUROCOLUMBUS - has performed an analysis using a Computational Fluido-Dynamic (CFD) tool. The rack containing the water pump assembly and other electronic equipment has been chosen for the study. As far as the Fire Detection is concerned, the simulation intends to predict the flow field established in the rack by the ventilation system and the transport of smoke by this velocity field from a supposed point source.
Technical Paper

Microbial Contamination Control and Prevention During Space H/W Manufacturing and Assembly

1994-06-01
941310
Microorganism accumulation and growth onboard a spacecraft may impact adversely on crew efficiency and safety as well as system, subsystems and payload. The results of test campaigns performed at Alenia Spazio in Summer 1993 are reported here. From them, some simple and effective prevention methods to be applied during the manufacturing and integration phases of a pressurised spacecraft have been identified and are here discussed. Although data obtained from Earth experience may be considered useful, it is uncertain and unfit for space station operational lifespan. Therefore, it is necessary to build a model of the phenomenon, able to provide a series of quantitative data as a function of different parameters related to environmental characteristics, crew, and on-board activities.
Technical Paper

Architecture of the Environmental Control System for the Mini Pressurised Logistics Module

1994-06-01
941309
The Mini Pressurised Logistics Module (MPLM), a cooperative project between NASA and ASI that will be designed, developed, produced, integrated and delivered by Alenia, is a pressurised volume devoted to the resupply and return of Space Station (SS)containerized cargo requiringapressurised environment, via the National Space Transportation System (NSTS). As a servicer for the SS, the MPLM will have to accomplish several trips between Earth and SS in support of logistic needs. Since the active payloads launched with MPLM (freezers and refrigerators) require resources during the transportation phase inside the NSTS, the MPLM has the peculiar capacity to exchange power, data and fluids with the Orbiter before docking to SS. Once docked to SS, the MPLM will be required to provide its full performance, making use of the resources available from the SS Node; nevertheless, in this phase some of the MPLM functions are demanded from the SS.
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