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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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The design details are presented of a flight-type heat source reentry vehicle and heat exchanger compatible with the isotope Brayton power conversion system. The reference reentry vehicle and heat exchanger were modified, orbital and superorbital capability was assessed, and a complete set of detail design layout drawings were provided.
Simulations of selected earth orbital operations involving the shuttle orbiter and various modular space station components are examined. Data on the physical characteristics of these items, such as size, shape, and configuration, as well as the current operational concepts were obtained from NASA, MSC and from drawings and sketches. From these data numerical models were developed for the space shuttle orbiter and components of a six-man initial station including a core module, power module with solar arrays, representative station modules, and various sensors and antenna. Also included are maintenance inspection and failure reports, discussions with operating and service personnel, and a detailed examination of the equipment. No incipient long term reliability problems were found.
Processing of electric power has been presented as a discipline that draws on almost every field of electrical engineering, including system and control theory, communications theory, electronic network design, and power component technology. The cost of power processing equipment, which often equals that of expensive, sophisticated, and unconventional sources of electrical energy, such as solar batteries, is a significant consideration in the choice of electric power systems.
A preliminary mechanical design of a complete lift fan engine system is reported. A description of the lift fan engine, layout drawings of the components and complete engine, and a discussion of the design analyses and results are presented. The design features and areas of analysis include fan and compressor rotor blades of composite construction, a combustor folded over the compressor, relatively high-temperature blades in the high-pressure turbine, the first stage of the low-pressure turbine used for bearing support and ducting of lubricant to the bearings, a complete lubrication system, critical speeds of the shafting, and vibration and flutter of the blading.
The separation concept for stage separation of parallel staged space shuttle vehicles is discussed. The forward link separation concept is emphasized. The effects of aerodynamic interference and component mass are analyzed. Qualitative measurements used to perform a preliminary evaluation of various separation system concepts are presented. Line drawings are included to clarify the mechanisms and spacecraft structures used in stage separation.
The specifications for the electrothermal hydrazine thruster model are presented including performance, design and qualification requirements, and product configuration and acceptance tests. The contamination control procedures, acceptance test plan, and engineering drawings are included.
Work is reported for fabricating and testing the fiberglass overwrapped titanium pressure vessel for cryogenic service. Difficulties encountered in the tank liner fabrication phase involved explosive forming, vacuum annealing, chemical milling and electron beam welding. While each of these processes and the nondestructive test methods employed are normally considered to be individually reliable, the combination of poor material together with fabrication and development reversals prevented the full achievement of the desired end results. Eight tanks plus a prototype and tool proofing article were produced. Six of the vessels failed during the hydrostatic sizing operation. One of the remaining tanks was hydrostatically pressurized to burst and the other was pressurized repeatedly at 75 F from 100 psi to the operating pressure until failure occurred. As a result, it is not possible to draw firm conclusions as to the true value of the design concept due to the problems encountered in the program.
The distance from the sun to the center of the star, Gamma Velorium, is determined in an effort to draw a physical model and identify the ionized energy source of the Gum nebula. The distance is calculated from the local hydrogen density of radio astronomy studies and the hydrogen measure.
Design and fabrication parameters of a lunar surface magnetometer are discussed. Drawings and requirements for mechanical design, electronic packaging design, thermal design, quality assurance and systems testing are included.
The design, fabrication, and testing of two types of IMPATT diode reflection amplifiers and a transmission amplifier are given. The Ku-band IMPATT diode development is discussed. Circuitry and electrical performance of the final version of the Ku-band amplifier is described. Construction details and an outline and mounting drawing are presented.
The manufacturer, tester, retailer, consumer, repairer disposer, trade and professional associations, national and international standards bodies, and governments in several roles are all involved in consumer product safety. A preliminary analysis, drawing on system safety techniques, is utilized to distinguish the inter-relations of these many groups and the responsibilities that they are or could take for product safety, including the slow accident hazards as well as the more commonly discussed fast accident hazards. The importance of interactive computer aided information flow among these groups is particularly stressed.
A list is presented of the facilities and environmental measurements to be monitored in support of the Apollo/Saturn vehicle AS-511. The measurement identification number, description, transducer operating range, recorder type and drawings illustrating measurement location are included. The following launch complex 39 facilities will be used on this vehicle: launch complex 39 pad A, and launcher umbilical tower number 3.
Four different structural problems are solved to gain familiarity with the NASTRAN computer program. The problems are: (1) a simply-supported beam subjected to lateral loads, (2) a rotating filamentary composite bar under the action of centrifugal forces, (3) a missile body with aerodynamic, gravitational, and inertial forces, and (4) a square simply-supported plate with in-plane temperature changes capable of buckling the plate. Input and output data are given for each problem. The results are compared with those obtained by other methods. However, except for the examples employing beam elements in which the agreement is excellent, the element breakup chosen for convenience in obtaining program familiarity is too coarse to draw conclusions regarding the program accuracy. The example problems disclosed errors in the plotting and thermal-buckling routines of the program.
Procurement specifications to provide vendors of space systems with supporting information to accurately price the selected major buy items are illustrated. In performing this task, rigid constraints on specifications and drawing details are avoided beyond those necessary to define basic requirements. Described are digital processing equipment, mass spectrometer, body mass measuring device, sensors, bio-belt power source, vision tester and instrumentation for a biochemical station.
The design and operation of a quad redundant data terminal and a multiplexer/demultiplexer (MDU) is described. The most unique feature is the design of the quad redundant data terminal. This is one of the few designs where the unit is fail/op, fail/op, fail/safe. Laboratory tests confirm that the unit will operate satisfactorily with the failure of three out of four channels. Although the design utilizes state-of-the-art technology, the waveform error checks, the voting techniques, and the parity bit checks are believed to be used in unique configurations. Correct word selection routines are also novel. The MDU design, while not redundant, utilizes, the latest state-of-the-art advantages of light coupler and interested amplifiers. Much of the technology employed was an evolution of prior NASA contracts related to the Addressable Time Division Data System. A good example of the earlier technology development was the development of a low level analog multiplexer, a high level analog multiplexer, and a digital multiplexer. A list of all drawings is included for reference and all schematic, block and timing diagrams are incorporated.
Exceedance statistics of winds and gusts observed over Cape Kennedy with Jimsphere balloon sensors are described. Gust profiles containing positive and negative departures, from smoothed profiles, in the wavelength ranges 100-2500, 100-1900, 100-860, and 100-460 meters were computed from 1578 profiles with four 41 weight digital high pass filters. Extreme values of the square root of gust speed are normally distributed. Monthly and annual exceedance probability distributions of normalized rms gust speeds in three altitude bands (2-7, 6-11, and 9-14 km) are log-normal. The rms gust speeds are largest in the 100-2500 wavelength band between 9 and 14 km in late winter and early spring. A study of monthly and annual exceedance probabilities and the number of occurrences per kilometer of level crossings with positive slope indicates significant variability with season, altitude, and filter configuration. A decile sampling scheme is tested and an optimum approach is suggested for drawing a relatively small random sample that represents the characteristic extreme wind speeds and shears of a large parent population of Jimsphere wind profiles.
The development and characteristics of the Stellar Tracking Rocket Attitude Positioning (STRAP) system are discussed. The objective of the program was to produce eight sets of reliable flight hardware at a cost that was compatible with the typical sounding rocket mission. The flight system consists of: (1) the attitude control system, (2) the pneumatics systems components, and a fine guidance error sensors star tracker. The performance of the system and the areas where improvements are needed are examined. Line drawings and circuit diagrams are presented to amplify the accomplishments of the project.
A brief summary of salient science results obtained from the Mariner 9 mission through June 1972 are presented. The data are presented in the form of photographs, line drawings and graphs. Emphasis is placed on the composition of the south polar cap, the surface of the satellites, and the presence of clouds in the atmosphere. The size and configuration of topographical features are compared with similar earth structures for reference.