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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Steel friction and wear tests in nitrogen with paraffinic resins, synthetic paraffinic oil, glycol, and ester lubricants including thermal stability at high temperatures
Tests of cryo-formed spheres to determine suitability as replacements for titatium helium storage bottles in liquid hydrogen tanks of saturn S-4B stage
Prototype auxiliary propulsion subsystem with isolated single tank propellant feed system and 5-cm-diameter ion thruster
Rate of meteoroid penetration of thin beryllium copper detector measured in near-lunar environment by Lunar Orbiter spacecraft
Existance of 5 minute oscillations in solar photospheric and low chromospheric magnetic fields
Earth radiation budget measurements, noting planetary albedo, IR radiant emittance and net balance
Super metal rich K giant stars atmospheric model, obtaining abundances and turbulent velocity parameter
Ion thrustor technology and subsystem development program status, describing design and performance characteristics
Integrated circuit life testing, comparing functional and pin-to-pin screening data
Apollo 11 and 12 lunar rocks and soil chemical composition, considering petrogenesis and major and trace elements abundance
Bulk elemental composition of Apollo 12 samples of lunar igneous and breccia rocks and soils from instrumental and radiochemical neutron activation analysis
Rare earth elements and trace elements abundance in Apollo 12 igneous rocks, breccia and lunar soil
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Nimbus, Tiros, and ESSA satellite measurements of terrestrial radiation budget
The alloys Nimonic 90, IN 100, coated IN 100, B 1900, coated B 1900, MAR M200, and MAR M200DS (directionally solidified) were studied. Maximum temperatures ranged from 770 C to 1120 C (1420 F to 2050 F). Specimen geometries included tapered disks, double-edged wedges, and cambered airfoils. The disks and wedges were heated and cooled in fluidized beds. The airfoil specimens were heated by a Mach 1 natural gas burner and rapid-air-cooled, with and without spanwise loading. Life calculations included two distinct failure modes: conventional low cycle fatigue and cyclic creep. Required material properties were limited to conventional thermal, tensile, and creep rupture data. The complete life calculation system included the calculation of transient temperature distributions, thermal strains, stresses, creep damage, fatigue damage, and cycles to first crack. Calculated lives were within a factor of two for 76 of the 86 data points analyzed. Cyclic creep accounted for 81% of all the calculated damage.
All system components were tested for endurance and steady state and cyclic operation. The following results were obtained: acceleration system (electrostatic type), 3100 hours continuous running; acceleration system (translation type), 2026 hours continuous running; cathode-isolator-vaporizer assembly, 5000 hours continuous operation and 190 restart cycles with 1750 hours operation; mercury expulsion system, 5000 hours continuous running; and neutralizer, 5100 hours continuous operation. The results of component optimization studies such as neutralizer position, neutralizer keeper hole, and screen grid geometry are included. Extensive mapping of the magnet field within and immediately outside the thruster are shown. A technique of electroplating the molybdenum accelerator grid with copper to study erosion patterns is described. Results of tests being conducted to more fully understand the operation of the hollow cathode are also given. This type of 5-cm thruster will be space tested on the Communication Technology Satellite in 1975.
Following the establishment of the overall transport concept, a study of all of the life limiting constraints associated with the transport were analyzed using modeling techniques. These design techniques included: (1) a response analysis from which the performance of the transport could be determined under operating conditions for a variety of conceptual variations both in a new and aged condition; (2) an analysis of a double cone guidance technique which yielded an optimum design for maximum guidance with minimum tape degradation; (3) an analysis of the tape pack design to eliminate spoking caused by negative tangential stress within the pack; (4) an evaluation of the stress levels experienced by the magnetic tape throughout the system; (5) a general review of the bearing and lubrication technology as applied to satellite recorders and hence the recommendation for using standard load carrying antifriction ball bearings; and (6) a kinetic analysis to determine the change in kinetic properties of the transport during operation.
A modified Hughes SIT-5 system is being tested for durability at the Lewis Research Center. As of October 1, 1972, the thruster subsystem has logged over 8000 hours of operation. The initial 2023 hours were run with a translating screen thrust vector grid. The thruster is currently operating with an electrostatic type vector grid. Profiles and maps taken at widely separated intervals show that performance and operating characteristics have remained essentially constant. Overall efficiency is about 32 percent and power to thrust ratio is 170 watts per millipound at a specific impulse of 2500 seconds. Telescopic examination of the vector grid shows some sputtering erosion due to charge exchange and direct impingement ions.