Search Results

In the design of spacecraft, heat transfer becomes a criterion of operation to maintain structural and equipment integrity over long periods of time. ...In the design of spacecraft, heat transfer becomes a criterion of operation to maintain structural and equipment integrity over long periods of time. The spacecraft thermal balance between cold space and solar, planetary, and equipment heat sources is the means by which the desired range of equipment and structural temperatures are obtained. ...With the total spacecraft balance set, subsystem and component temperatures can be analyzed for their corresponding thermal requirements.

A submerged membrane biological reactor (MBR) was evaluated for treatment of a spacecraft wastewater analog. The aerobic MBR (a modified CSTR) had a 12 L working volume, submerged 0.2 μm membrane filter, 12.6 h hydraulic retention time (simulated 2 person crew), and infinite solids retention time.

This paper attempts to expand the knowledge in beryllium mechanical joining technology to develop a structural and fabrication confidence level in utilizing solid shank and blind rivet fasteners in assembling beryllium spacecraft structures.

As a part of a program jointly supported by the USAF and Canada's Department of National Defense, BlueStar is developing large (50 to 100-Ah)lithium ion cells for aircraft and spacecraft applications. Presently, 20-Ah cells are being developed as the first stage of the scale-up process and the design of these cells involves several tradeoffs related to the specific nature of this application.

Research was initiated due to increased concern over trace contaminant gas build-up in an enclosed atmosphere of a spacecraft for long duration space flights. A gas mixture simulating conditions on long duration space missions must be created in order to test trace contaminant control hardware. ...This contaminant model gas mixture can be used to test trace contaminant control hardware for an enclosed spacecraft environment.

“Tinned Copper Braid” is planned to be used in IRS-1C spacecraft for the thermal control of the detector of the “Middle Infra Red” (MIR) band of LISS III Camera.

Controlling microbial growth and biofilm formation in spacecraft water-distribution systems is necessary to protect the health of the crew. Methods to decontaminate the water system in flight may be needed to support long-term missions. ...The biofilms were developed by placing the coupons in a manifold attached to the effluent line of a simulated spacecraft water-distribution system. After biofilms were established, the coupons were removed and placed in a treatment manifold in a separate water treatment system where they were exposed to the chemical treatments for various periods.

The properties of the prepared nanofluids will allow for lighter, smaller, and higher efficiency spacecraft thermal control systems to be developed. Nanofluids with spherical or rod-shaped metal nanoparticles were investigated.

An aqueous phase catalytic oxidation system (APCOS) was designed, tested and delivered to NASA/Johnson Space Center (JSC). The APCOS removes residual organic impurities in reclaimed water to a level acceptable for potable use and to provide disinfection. The reactor, which contains a heterogeneous catalyst consisting of a noble metal on an inert support medium, operates at 120 - 150 °C and at fluid pressures of several atmospheres to maintain an aqueous liquid phase. Pressurized gaseous oxygen, used as the oxidant, is directly injected into the liquid phase. A description of the subsystems process hardware is presented. The APCOS was demonstrated to mineralize organic impurities at concentrations of 100 mg/L total organic carbon (TOC) to < .5 mg/L (<500 μg/L TOC). In addition, disinfection features were demonstrated with microbial challenge tests.

Electrical power savings are recurrent design drivers for Solar system exploration spacecraft. This is particularly applicable to the French mission “Mars Orbiter 2007” which consists in sending four Martian probes, after a one year cruise and before orbiting three years around the red planet. ...Thus, a huge effort shall be made to minimize this spacecraft heating power demand. This challenge is less to limit the heating power inside the vehicle, for which proven systems exist, than to lower the heating power demand of the outer elements. ...Indeed, these external units, mainly chemical propulsion thrusters, potentially require a heating power reaching nearly 10% of the spacecraft electrical budget. Consequently, the concept chosen to match the power optimization target consists in maintaining the spacecraft body temperature around 25°C thanks to a classical VCHP network itself regulated by a closed-loop control of the non condensable gas tank temperatures.

This work describes the microbiological assessment and materials compatibility of a silver-based biocide as an alternative to iodine for the Crew Exploration Vehicle (CEV) and future spacecraft potable water systems. In addition to physical and operational anti-microbial counter-measures, the prevention of microbial growth, biofilm formation, and microbiologically induced corrosion in water distribution and storage systems requires maintenance of a biologically-effective, residual biocide concentration in solution and on the wetted surfaces of the system. ...This work reports the efficacy of [500 ppb] silver fluoride in potable water as a biocide against each of five bacterial species previously isolated from spacecraft and the materials compatibility of the biocide with each of three heritage materials used in US spacecraft potable water systems (i.e., Inconel 718, 21-6-9 Stainless Steel (aka Nitronic 40), and 316 Stainless Steel). ...This work reports the efficacy of [500 ppb] silver fluoride in potable water as a biocide against each of five bacterial species previously isolated from spacecraft and the materials compatibility of the biocide with each of three heritage materials used in US spacecraft potable water systems (i.e., Inconel 718, 21-6-9 Stainless Steel (aka Nitronic 40), and 316 Stainless Steel).

Microbial control in spacecraft is currently achieved by environmental control of humidity, forced air filtration, and the use of antimicrobials for surface application (i.e., isopropyl alcohol) and biocidal agents for treatment of potable and technical water supplies (e.g., iodine and iodide or ionic and colloidal silver). ...To assess its suitability in spacecraft applications, we previously employed a test method to assess the effectiveness of aminosilane coatings on textiles. ...Reduction in the bacterial load and/or cell viability of bacteria in the reservoir was observed (less than 10 CFU/mL), providing support for the use of aminosilane coatings to prevent microbial contamination of spacecraft environmental systems.

Microbial biofilms representing both Gram-positive and Gram-negative bacteria were artificially coated onto aluminum metal surfaces that are commonly used in building spacecraft. Changes in bacterial numbers were monitored over time on metal test sections by conventional spread plate technique and polymerase chain reaction (PCR). ...In ongoing investigations to map and archive the microbial footprints in various components of spacecraft and its accessories, we examined the microbial populations of the JPL-Spacecraft Assembly Facility (SAF). ...We exposed witness plates that are made up of spacecraft materials and/or painted with spacecraft-quality paints for ~7 to 9 months. In the initial studies reported here, we examined the total cultivable aerobic heterotrophs.

The Near Earth Asteroid Rendezvous spacecraft is the first to launch of the NASA Discovery programs. Its power subsystem is a direct energy transfer architecture with a Super™ nickel cadmium battery and four fixed solar panels populated with gallium arsenide on germanium solar cells.

The ability of iodine to maintain microbial water quality in a simulated spacecraft water system is being studied. An iodine level of about 2.0 mg/L is maintained by passing ultrapure influent water through an iodinated ion exchange resin.

The ability of iodine to control microbial contamination and biofilm formation in spacecraft water distribution systems is being studied. Two stainless steel water subsystems are being used.

Two simulated spacecraft water systems are being used to evaluate the effectiveness of iodine for controlling microbial contamination within such systems.

Nowadays, as weight savings is mandatory, this paper describes all the benefits of “C” springs and “S” springs for vehicles and spacecraft applications.

Archived water samples collected on the International Space Station (ISS) and returned to Earth for analysis have, in a few instances, contained trace levels of heavy metals. Building on our previous advances using Colorimetric Solid Phase Extraction (C-SPE) as a biocide monitoring technique [1, 2], we are devising methods for the low level monitoring of nickel(II), lead(II) and other heavy metals. C-SPE is a sorption-spectrophotometric platform based on the extraction of analytes onto a membrane impregnated with a colorimetric reagent that are then quantified on the surface of the membrane using a diffuse reflectance spectrophotometer. Along these lines, we have analyzed nickel(II) via complexation with dimethylglyoxime (DMG) and begun to examine the analysis of lead(II) by its reaction with 2,5-dimercapto-1, 3, 4-thiadiazole (DMTD) and 4-(2-pyridylazo)-resorcinol (PAR).

In the design of spacecraft, heat transfer becomes a criterion of operation to maintain structural and equipment integrity over long periods of time. ...In the design of spacecraft, heat transfer becomes a criterion of operation to maintain structural and equipment integrity over long periods of time. The spacecraft thermal balance between cold space and solar, planetary, and equipment heat sources is the means by which the desired range of equipment and structural temperatures are obtained. ...With the total spacecraft balance set, subsystem and component temperatures can be analyzed for their corresponding thermal requirements.