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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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At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
NASA NTRS1971

Pyrotechnic hazards classification and evaluation program. Electrostatic vulnerability of the E8 and XM15/XM165 clusters, phase 2

An investigation into the electrostatic phenomena associated with the manufacturing and handling of explosives is discussed. The testing includes measurement of the severity of the primary charge generation mechanism, triboelectric effects between dissimilar surfaces; refinement of equivalent circuits of the XM15/XM165 and E8 fuse trains; evaluation of the electrostatic spark discharge characteristics predicted by an equivalent circuit analysis; and determination of the spark ignition sensitivity of materials, components, junctions, and subassemblies which compose the XM15/XM165 and E8 units. Special studies were also performed. These special tests included ignition sensitivity of the complete XM15 fuse train when subjected to discharges through its entire length, measurement of electrostatic potentials which occur during the E8 foaming operation during fabrication, and investigation of the inadvertent functioning of an XM15 cluster during manufacturing. The test results are discussed and related to the effectiveness of suggested modification to reduce the electrostatic ignition sensitivity.

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NASA NTRS1972

Apollo experience report: Lunar module environmental control subsystem

A functional description of the environmental control subsystem is presented. Development, tests, checkout, and flight experiences of the subsystem are discussed; and the design fabrication, and operational difficulties associated with the various components and subassemblies are recorded. Detailed information is related concerning design changes made to, and problems encountered with, the various elements of the subsystem, such as the thermal control water sublimator, the carbon dioxide sensing and control units, and the water section. The problems associated with water sterilization, water/glycol formulation, and materials compatibility are discussed. The corrective actions taken are described with the expection that this information may be of value for future subsystems. Although the main experiences described are problem oriented, the subsystem has generally performed satisfactorily in flight.

Gillen, R. J.↗
NASA NTRS1972

Thermo-mechanical design aspects of mercury bombardment ion thrusters.

The mechanical design criteria are presented as background considerations for solving problems associated with the thermomechanical design of mercury ion bombardment thrusters. Various analytical procedures are used to aid in the development of thruster subassemblies and components in the fields of heat transfer, vibration, and stress analysis. Examples of these techniques which provide computer solutions to predict and control stress levels encountered during launch and operation of thruster systems are discussed. Computer models of specific examples are presented.

Schnelker, D. E.↗
NASA NTRS1973

Payloads.

Approaches to payload definition, design, and planning adopted in the Space Shuttle Program are described. The Space Shuttle offers many new modes of operation featuring reuse of spacecraft, on-orbit checkout and maintenance, sortie experiment missions, and opportunities to trade launch weight and volume for cost savings. In order to take advantage of these new approaches and to accommodate the varying missions, new payload elements have been identified, and new low-cost design approaches are being developed to utilize standardized components and modularized subassemblies that reduce spacecraft buildup and maintenance costs. A new payload planning technique makes use of the computer to provide large-scale planning, scheduling, and costing required for various program options.

Marshall, W. R.↗
NASA NTRS1973

Electronic control circuits: A compilation

A compilation of technical R and D information on circuits and modular subassemblies is presented as a part of a technology utilization program. Fundamental design principles and applications are given. Electronic control circuits discussed include: anti-noise circuit; ground protection device for bioinstrumentation; temperature compensation for operational amplifiers; hybrid gatling capacitor; automatic signal range control; integrated clock-switching control; and precision voltage tolerance detector.

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NASA NTRS1971

A Saturn launched X-ray astronomy experiment. Volume 2: S-150

In order to develop an experiment which would provide previously unknown information at the projected new launch period, a decision was made to modify the S-027 experiment to allow detection of lower energies which had previously not been mapped. The modification basically required that the static counters be replaced with a thin film entrance window gas flow counter which would allow detection of X-ray energies as low as 150 ev. The new experiment designated S-150 was designed to detect X-ray energies over a spectrum of 150 ev to 10 Kev. Photographs of the S-150 experiment are shown. Basically the same signal detection and processing techniques were used on the S-150 experiment as were used on the S-027. For economic reasons much of the S-027 subassembly hardware was used on the new experiment. The main design changes were in the signal detection system and the high energy veto system.

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NASA NTRS1973

Liquid rocket valve assemblies

The design and operating characteristics of valve assemblies used in liquid propellant rocket engines are discussed. The subjects considered are as follows: (1) valve selection parameters, (2) major design aspects, (3) design integration of valve subassemblies, and (4) assembly of components and functional tests. Information is provided on engine, stage, and spacecraft checkout procedures.

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NASA NTRS1973

RI 1170 advanced strapdown gyro

The major components of the RI 1170 gyroscope are described. A detailed functional description of the electronics including block diagrams and photographs of output waveshapes within the loop electronics are presented. An electronic data flow diagram is included. Those gyro subassemblies that were originally planned and subsequently changed or modified for one reason or another are discussed in detail. Variations to the original design included the capacitive pickoffs, torquer flexleads, magnetic suspension, gas bearings, electronic design, and packaging. The selection of components and changes from the original design and components selected are discussed. Device failures experienced throughout the program are reported and design corrections to eliminate the failure modes are noted. Major design deficiencies such as those of the MSE electronics are described in detail. Modifications made to the gas bearing parts and design improvements to the wheel are noted. Changes to the gas bearing prints are included as well as a mathematical analysis of the 1170 gas bearing wheel by computer analysis. The mean free-path effects on gas bearing performance is summarized.

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NASA NTRS1974

Surface composition mapping radiometer instrument

The design, development, and fabrication of a three-channel scanning radiometer are discussed. The instrument was flown on Nimbus 5 satellite and measured infrared energy in the 8.3 to 9.3, 10.2 to 11.2, and 0.8 to 1.1 micron spectral regions. The instrument parameters are presented. Theoretical discussions of the instrument subassemblies are provided. Operational details of the mechanical and electrical portions of the instrument are included.

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NASA NTRS1974

Design manual: Oxygen Thermal Test Article (OTTA)

The characteristics of a cryogenic tank for storing liquid hydrogen, nitrogen, oxygen, methane, or helium for an extended period of time with minimum losses are discussed. A description of the tank and control module, assembly drawings and details of major subassemblies, specific requirements controlling development of the system, thermal concept considerations, thermal analysis methods, and a record of test results are provided. The oxygen thermal test article thermal protection system has proven that the insulation system for cryogenic vessels is effective.

Chronic, W. L.↗
NASA NTRS1973

An engineering model 30 cm ion thruster

Thruster development at Hughes Research Laboratories and NASA Lewis Research Center has brought the 30-cm mercury bombardment ion thruster to the state of an engineering model. This thruster has been designed to have sufficient internal strength for direct mounting on gimbals, to weigh 7.3 kg, to operate with a corrected overall efficiency of 71%, and to have 10,000 hours lifetime. Subassemblies, such as the ion optical system, isolators, etc., have been upgraded to meet launch qualification standards. This paper presents a summary of the design specifications and performance characteristics which define the interface between the thruster module and the remainder of the propulsion system.

Poeschel, R. L.↗
NASA NTRS1973

Optical alignment of a 0.5 meter ultra-violet spectrometer for Apollo 17

Description of the design and performance of a 0.5 m Ebert spectrometer mounted on Apollo 17 for research on the ultraviolet spectrum of the lunar atmosphere. The instrument was designed for operation in the range 1175 to 1675 A. A method was developed for aligning subassemblies in such a way that the assembled instrument would be aligned in the ultraviolet to an accuracy of 2 A with maximum efficiency.

Schroader, I. H.↗
NASA NTRS1975

Networks systems and operations

The application of wideband communication techniques for data links with satellites is discussed. A diagram of the demand assigned voice communications system is provided. The development of prototype integrated spacecraft paramps at S- and C-bands is described and the performance of space-qualified paramps is tabulated. The characteristics of a dual parabolic cylinder monopulse zoom antenna for use with the tracking and data relay satellite system (TDRSS) are analyzed. The development of a universally applicable transponder at S-band is reported. A block diagram of the major subassemblies of the S-band transponder is included. The technology aspects of network timing and synchronization of communication systems are to show the use of the Omega navigation system. The telemetry data compression system used during the Skylab program is evaluated.

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NASA NTRS1975

Preliminary vibration, acoustic, and shock design and test criteria for components on the HEAO-A spacecraft

These vibration, acoustic, and shock specifications provide the qualification test criteria for spacecraft components and subassemblies and for the High Energy Astronomy Observatory (HEAO-A) experiments. The HEAO-A was divided into zones and subzones to obtain simple component groupings. Zones are designated primarily to assist in determining the applicable specification. A Subzone is available for use when the location of the component is known but component design and weight are not well defined. When the location, weight, and mounting configuration of the component are known, the appropriate Subzone weight ranges are available. Experiment and specific component specifications are available.

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NASA NTRS1975

Limb radiance inversion radiometer

Engineering and scientific objectives of the LRIR experiment are described along with system requirements, subassemblies, and experiment operation. The mechanical, electrical, and thermal interfaces between the LRIR experiment and the Nimbus F spacecraft are defined. The protoflight model qualification and acceptance test program is summarized. Test data is presented in tables to give an overall view of each test parameter and possible trends of the performance of the LRIR experiment. Conclusions and recommendations are included.

Drozewski, R. W.↗
NASA NTRS1975

ATM CMG/EPEA

The Apollo Telescope mount double gimballed control moment gyro ATM CMG is described. Photographs of the CMG and its subassemblies are presented along with a functional block diagram of the CMG subsystem. Analog processing electronics for ATM vehicle pointing control and ATM experiment package pointing control are also described.

Abramowitz, R.↗
NASA NTRS1974

The design and development of a high voltage power supply

A high voltage circuit system was redesigned, breadboarded, and tested to meet revised specification requirements. Circuit component subassemblies are described and include the firing unit, regulator, dc to dc converter, and output and trigger circuits. Design changes, tests, and equipment fabrication are outlined chronologically by month. A list of design specifications is included.

Ting, R.↗
NASA NTRS1975

Preliminary vibration, acoustic, and shock design and test criteria for components on the HEAO-C spacecraft

The vibration, acoustic, and shock specification test criteria for spacecraft components and subassemblies and for the high Energy Astronomy Observatory (HEAO-C) experiments are presented. The HEAO-C was divided into zones and subzones to obtain simple component groupings. Zones are designated primarily to assist in determining the applicable specification. A subzone (general specification) is available for use when the location of the component is known but component design and weight are not well defined. When the location, weight, and mounting configuration of the component are known, the appropriate subzone weight ranges (-A, -B, etc. ) are available. Experiment and specific component specifications are available.

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