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The paper reviews one of the possible approaches to developing an analysis technique of Oxygen Generation System (OGS) thermal conditions. As an object of simulation a 30% KOH water electrolysis system with forced electrolyte circulation through the both electrolyzer chamber followed by separation of a gas/liqiud mixture using hydrophobic porous membranes. A formalized description of the key system components (an electrolyzer, set of coolers, separator, canister) is presented. A mathematical model simulating stationary and non-stationary thermal conditions of the system is constructed and its programming is reviewed. Some results of computational and operational experiments obtained for checking the model adecuacy are presented.

Hamilton Standard Space Systems International, Inc. (HSSSI) has obtained and is currently testing a variety of Russian life support hardware. These units have been or are contemplated for use on Mir I and II space stations. This paper presents the current status of performance testing of a Sabatier Carbon Dioxide Processing Unit (CDPU) and components of a Potable Water Processing System (PWP). These systems were fabricated by NIICHIMMASH, the supplier of these units to the Russian space program. It is the intent of this testing program to obtain a data base for technology comparisons to support planned and future international missions. For the CDPU, reactant conversion efficiencies in excess of 99 percent have been noted for the variation in test conditions with 2 to 6 man processing (flows) tested. The CDPU's effluent water has been produced at anticipated rates and is relatively contaminant free.

The paper reviews some problems of providing the thermal conditions in the Sabatier reactor of the CO2 processing system designed to be operated on Russia's service module of ISSA. The possibility of providing and maintaining the autothermal process with heat removal off the canister surface enclosing the reactor. Some results of control system checks in the start-up, steady-state and shutdown modes are presented. The results of Russia's hardware undergone testing onsite at Dornier (Germany) and Hamilton Standard (U.S.) are discussed.

This paper reviews designs of urine distillation systems for spacecraft water recovery. Consideration is given to both air evaporation and vacuum distillation cycles, to the means for improving cycle performance (such as heat pumps, multistaging, and rotary evaporators), and to system concepts offering promise for future development. Vacuum distillation offers lower power consumption, at some increase in system complexity; air evaporation distillation is capable of providing higher water recovery efficiency, which could offset the lower power consumption advantage of vacuum distillation for long-duration missions.

The paper is devoted to consideration of the possible approach to forecasting functioning physico/chemical Regenerative Life Support Systems (RLSS) in regular and off-normal conditions of operation on the basis of methods of mathematical simulation. Prediction of RLSS functioning under operating conditions represents the special interest for the analysis of off-normal situations, caused by development of a resource or presence that or that or of the other of failure of the equipment, or change of external conditions. In the given situations working mechanisms of transfer of mass and energy change not only characteristic and modes of operations of separate apparatus, but also, in a number of cases. The given peculiarities should be taken into account at formation of the formalized descriptions of the RLSS hardware.

Development of closed life support systems for water recovery, oxygen generation and food processing is achievable in the future. However, currently the possibility of partial reproduction of food components from metabolic products and biocomplex waste should be taken into account when advanced life support system development is under consideration. Studies on carbohydrate synthesis from products of life are of particular interest because carbohydrates hold the first place in terms of mass in the food. The paper discusses possible ways of carbohydrate synthesis by physical/chemical means. Separate stages of a carbohydrate synthesis process are considered.

Simulated spacecraft water recovery wastewater feed streams were purified with a three-stage vacuum rotary distillation processor (TVRD) during a series of tests conducted to evaluate the operation of this technology. The TVRD was developed to efficiently reclaim potable water from urine in microgravity by NIICHIMMASH (Moscow, Russia). A prototype was evaluated at the Honeywell Space Water Reclamation test lab, where a special test setup was assembled to evaluate the performance of the TVRD. This paper discusses the TVRD technology, test description, test results, and performance analysis. Tests were conducted using four streams of wastewater: pretreated human urine, bioprocessor effluent, reverse osmosis brine ersatz, and deionized water. The testing demonstrated that greater than 90 percent water recovery can be reached with production rates of 2.2 to 2.9 kg/hr (4.84 to 6.30 lb/hr).

The research conducted at NIICHIMMASH for the past several years in the area of Integrated Life Support System (ILSS) strategy development for technology efficiency analysis and system structure synthesis is reviewed in this paper. This study proposes an generalized efficiency model for ILSS development, which includes global, thermodynamic and local quantitative and qualitative factors. The research resulted in a strategy for the synthesis of ILSS structure based on evolutionary and integral- hypothhetical approaches. This strategy allows development of new system configurations, evaluation of existing ILSS effectiveness and considers decision marker's (DM) preferences. Uncertainty in the initial information about properties of the system or technology has a big influence on DM making decisions about future system appearance. Fuzzy set theory is used to define the uncertainty in the initial information.

This paper reviews a Crew Simulation Model (CSM) for Space Vehicle Integrative Life Support System (ILSS) operation study. It is designed to simulate crew metabolic reaction mass and energy flows in accelerated time mode with each crew member specifics consideration. This CSM formally is based on human body general simulation, which includes main functional systems like: the cardiac-vascular, external respiration, thermal regulation and water/mineral balance. Work and rest time schedules are also considered as well as each crew member presence in a particular module. The CSM considers trace contaminants in metabolic products due to nutrition and environment temperature. This simulations' formal review is shown in the paper as well as formal implementation with computed experiment results. Some of the possible applications are also approached.

This paper reviews the development and testing of the distillation subsystem of water regeneration system from urine (WRS-UM) based on a method of vacuum distillation with a rotary multistage vacuum distiller and a thermal pump. Test results show that with relatively small power consumption the subsystem using rotary three-stage vacuum distiller provides high rates of heat and mass transfer processes, useful productivity and distillate quality. The conducted tests have confirmed that it will be efficient to use the presented system as a part of WRS-UM system in Russian segment of the International Space Station.