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Technical Paper

“SODART” Telescope Silicon Detector Cooling System (Thermal Test Results of the Scale-Down Model)

1992-07-01
921365
The onboard “SODART” telescope silicon detector cooling system of the “Spectrum-X-Gamma” observatory, which is designed for the space objects X-ray radiation study, is described. The scale-down model of the passive cooling system description and thermal vacuum test results of this model are given. In the real cooling system the minimal detector temperature at 300 mW heat release is expected about 107 K.
Technical Paper

‘Skins’ by Design: Humans to Habitats

2003-07-07
2003-01-2655
Whether we live on land, underwater, or out there in space, what makes it possible is our ‘skin’. The one we were born with, the one we wear, the one we live in, and the one we travel in. The skin is a response to where we live: it protects as our first line of defense against a hostile environment; it regulates as part of our life-support system; and, it communicates as our interface to everything within and without. In the context of space architecture – we, our space suits, vehicles and habitats are all equipped with highly specialized ‘skins’ that pad us, protect us and become an integral part of the design expression. This paper approaches the subject from a holistic perspective considering ‘skins’ and their manifestation as structure, as vessel, as texture, and as membrane. The paper then goes on to showcase innovative use of materials in practice through two case studies: the ‘spacesuit’ and ‘inflatable habitats’.
Technical Paper

β-Carotene Content of Dehydrated Hydroponic Sweetpotatoes Grown under Different Lighting Conditions

2007-07-09
2007-01-3051
The sweetpotato (Ipomoea batatas L. LAM.) is a versatile and underexploited food crop. Consumption of sweetpotato based processed foods provide β-carotene, which is the major precursor of vitamin A. The sweetpotato has the potential to provide antioxidants that may help reduce the radiation risks astronauts face while in space. Therefore the objective of this experiment was to evaluate β-carotene in dehydrated hydroponic sweetpotato cultivars. Hydroponic cultivars WHATLEY/LORETAN and NCC-58 were grown with and without 7-10 μmole of light. WHATLEY/LORETAN contained the highest amount of β-carotene content average of 31 μg/100g in dehydrated hydroponic sweetpotatoes compared to NCC-58 with 18.5 μg/100g.
Technical Paper

the behavior of Radiation-Resistant ANP TURBINE LUBRICANTS

1959-01-01
590051
RADIATION can produce almost instantaneous failure of modern aircraft lubricants, tests at Southwest Research Institute show. Two types of failures demonstrated are rapid viscosity rise and loss of heat conductivity. Furthermore, it was found that lubricants can become excessively corrosive under high-level radiation. Generally speaking, the better lubricants appeared to improve in performance while marginal ones deteriorated to a greater extent under radiation. When the better lubricants were subjected to static irradiation prior to the deposition test, there was a minor increase in deposition number as the total dose was increased.
Standard

electric Vertical Take Off and Landing (eVTOL) Emergency Lighting

2023-09-14
WIP
ARP8620
The purpose of this ARP is to provide criteria that will lead to and support existing regulatory standards of systems for UAM/AMM/eVTOL aircraft such that the emergency systems will facilitate egress under emergency conditions. Consideration is given to existing requirements of the FAA and to the recommendations of aircraft operators and those involved in the manufacture or use of the emergency lighting system. Occupant safety is the primary objective, with appropriate provisions for crew (pilot) system control taken into consideration. Consideration is also given to autonomous aircraft in which passengers are required to egress without the aid or direction of crew. The criteria established herein are intended to produce an emergency lighting system that will comply with the Federal and International Regulations. However, these recommendations are but one means of meeting the objective.
Technical Paper

eROSITA Camera Low Temperature Thermal Control

2008-01-29
2008-01-1957
eROSITA (extended ROentgen Survey with an Imaging Telescope Array) is a powerful X-ray telescope under development by the Max-Planck-Institut für extraterrestrische Physik (MPE) in Garching, Germany. eROSITA is the core instrument on the Russian SRG1 mission which is planned for launch in 2011. It comprises seven nested Wolter-I grazing incidence telescopes, each equipped with its own CCD camera. The mirror modules have to be maintained at 20°C while the cameras are operated at -80°C. Both, mirrors and CCDs have to be kept within tight limits. The CCD cooling system consists of passive thermal control components only: two radiators, variable conductance heat pipes (VCHP) and two special thermal storage units. The orbit scenario imposes severe challenges on the thermal control system and also on the attitude control system.
Technical Paper

considerations of some JET-DEFLECTION PRINCIPLES for - - directional control - - lift

1958-01-01
580062
THE performance characteristics of various devices applicable for jet directional control, lift augmentation, and VTOL-STOL studied at the NACA Lewis Laboratory are discussed, including jet deflection devices applicable to the conventonal round nozzle and novel nozzle configurations. The results indicate that many of the deflection devices applicable to conventional nozzles can readily be used for directional control or lift augmentation. Other deflection devices, such as movable plug, internal flap, cylindrical thrust reverser, swiveled primary with fixed shroud, and 90 deg side-bleed nozzle, are limited in application to jet directional control or aircraft trim because the loss in axial thrust for a given deflection force is prohibitive or the maximum deflected force obtainable is limited.
Technical Paper

byteflight~A new protocol for safety-critical applications

2000-06-12
2000-05-0220
The permanently increasing number of convenience and safety functions leads to higher complexity of in-car electronics and the rapidly growing amount of sensors, actuators and electronic control units places higher demands on high- speed data communication protocols. Safety-critical systems need deterministic protocols with fault-tolerant behavior. The need for on-board diagnosis calls for flexible use of bandwidth and an ever-increasing number of functions necessitates a flexible means of extending the system. None of the communication solutions available on the market until now (like CAN or TTP) have been able to fulfill all these demands. To solve these problems, BMW together with several semiconductor companies has developed a new protocol for safety-critical applications in automotive vehicles.
Technical Paper

Zone of Influence of Porous Suction Tubes in Condensing Heat Exchanger for Space Systems

2008-06-29
2008-01-2075
A “next generation” condensing heat exchanger for space systems has to satisfy demanding operational requirements under variable thermal and moisture loads and reduced gravity conditions. Mathematical models described here are used to investigate transient behavior of wetting and de-wetting dynamics in the binary porous system of porous tubes and porous cold plate. The model is based on the Richard's equation simplified for the zero-gravity conditions. The half-saturation distance or the zone of influence of the porous annular suction tubes on the cold-plate porous material will be in the range of 1 to 10 cm for the time scales ranging from 100 to 10,000 seconds and moisture diffusivity in the range of D = 10-4 to 10-6 m2/s.
Standard

Zinc Phosphate Treatment Paint Base

2019-05-17
CURRENT
AMS2480J
This specification covers the requirements for producing a zinc phosphate coating on ferrous alloys and the properties of the coating.
Technical Paper

Zero-Venting, Regenerable, Lightweight Heat Rejection for EVA Suits

2005-07-11
2005-01-2974
Future space exploration missions will require a lightweight spacesuit that expends no consumables. This paper describes the design and performance of a prototype heat rejection system that weighs less than current systems and vents zero water. The system uses regenerable LiCl/water absorption cooling. Absorption cooling boosts the heat absorbed from the crew member to a high temperature for rejection to space from a compact, non-venting radiator. The system is regenerated by heating to 100°C for two hours. The system provides refrigeration at 17°C and rejects heat at temperatures greater than 50°C. The overall cooling capacity is over 100 W-hr/kg.
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