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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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On-line central data processing system connected to time shared computer for recording data from test facilities, discussing hardware configuration, software considerations and advantages
Statistical techniques for selecting optimal test levels for vibration tests of spacecraft hardware
The lunar module display and control subsystem equipment is described with emphasis on major problems and their solutions. Included in the discussion of each item is a description of what the item does and how the item is constructed. The development, hardware history, and testing for each item are also presented.
A design and experimental program to develop special instrumentation systems, design engine hardware, and conduct tests using LOX/GH2 propellants in which the propellant flow stratification was controlled is described. The mixture ratio was varied from 4.6 to 6 overall. The mixture ratios in the core and outer zone were varied from 3.5 to 6 and 5 to 8, respectively. The range in boundary layer coolant was from 0 to 10 percent of the fuel. The nominal chamber pressure and thrust were 225 psia and 7000 pounds, respectively. Pressure and heat flux profiles as well as gas sampling of the exhaust products were obtained. Specific impulse efficiencies of approximately 94 percent and characteristic velocity efficiencies of approximately 97 percent were obtained during the experiments.
Explosive charges of various sizes were investigated for use in lunar seismic studies. Program logistics, and the specifications for procurement of bulk explosives are described. The differential analysis, thermal properties, and detonation velocity measurements on HNS/Teflon 7C 90/10 are reported along with the field tests of the hardware. It is concluded that nearly all large explosive charges crack after fabrication, from aging or thermal shock. The cracks do not affect the safety, or reliability of the explosives.
The L-band positioning experiment is reported which encompassed experiment design, experimentation, and data reduction and analysis. In the experiment the ATS-5 synchronous satellite L-band transponder was used in conjunction with the modified ALPHA 2 navigation receivers to demonstrate the technical capability of precision position fixing for oceanographic purposes. The feasibility of using relative ranging techniques implemented by two identical receiving systems, properly calibrated, to determine a line of position accurately on the surface of the earth was shown. The program demonstrated the level of resolution, repeatibility, precision, and accuracy of existing modest-cost effective navigation equipment. The experiment configuration and data reduction techniques were developed in parallel with the hardware modification tasks. Test results verify the ability of a satellite-based system to satisfy the requirements of precision position fixing.
Research and development programs in variable conductance heat pipe technology were conducted. The treatment has been comprehensive, involving theoretical and/or experimental studies in hydrostatics, hydrodynamics, heat transfer into and out of the pipe, fluid selection, and materials compatibility, in addition to the principal subject of variable conductance control techniques. Efforts were not limited to analytical work and laboratory experimentation, but extended to the development, fabrication and test of spacecraft hardware, culminating in the successful flight of the Ames Heat Pipe Experiment on the OAO-C spacecraft.
Current and past supersonic transport configurations are reviewed to assess redundancy requirements for future airplane control systems. Secondary actuators used in stability augmentation systems will probably be the most critical actuator application and require the highest level of redundancy. Two methods of actuator redundancy mechanization have been recommended for further study. Math models of the recommended systems have been developed for use in future computer simulations. A long range plan has been formulated for actuator hardware development and testing in conjunction with the NASA Flight Simulator for Advanced Aircraft.
Cryogenic auxiliary propulsion systems consist of five major subsystems: propellant tanks, propellant conditioning assemblies, accumulators, propellant distribution systems, and thrustors. The propellant conditioning assembly (PCA) converts low pressure liquid to high pressure gas for use by the thrustors, and is one of the most complex subsystems of the cryogenic propulsion system. The ability to achieve rapid starts and at the same time maintain system control are two critical areas of PCA operation. To investigate these critical areas of operation, a PCA of the general type required was designed, fabricated, and tested using existing hardware. Realistic start times were achieved and system control was maintained at all operating conditions.
The system is described as a computer-based system designed to track the status of problems and corrective actions pertinent to space shuttle hardware. The input, processing, output, and performance requirements of the system are presented along with standard display formats and examples. Operational requirements, hardware, requirements, and test requirements are also included.
Modal synthesis methods were developed for use by engineers for cost-effective solutions of large structural dynamics problems. Different methods were proposed by various investigators based upon comparative solutions of relatively simple structures using different forms of displacement functions. The application of modal synthesis methods to a large complex structure in a project environment is described. The considerations include analysis, hardware interfaces, schedules, tests, resources, and other project requirements. Good technical results were obtained through the use of an integrated analysis/test modal synthesis on both substructures and systems.
Regenerative processes for the revitalization of spacecraft atmospheres require an Oxygen Reclamation System (ORS) for the collection of carbon dioxide and water vapor and the recovery of oxygen from these metabolic products. Three life support subsystems uniquely qualified to form such an ORS are an Electrochemical CO2 Depolarized Concentrator (EDC), a CO2 Reduction Subsystem (BRS) and a Water Electrolysis Subsystem (WES). A program to develop and test the interface hardware and control concepts necessary for integrated operation of a four man capacity EDC with a four man capacity BRS was successfully completed. The control concept implemented proved successful in operating the EDC with the BRS for both constant CO2 loading as well as variable CO2 loading, based on a repetitive mission profile of the Space Station Prototype (SSP).
The four bladed pitch stirring rotor model was used in a rotor dynamic wake survey at zero advance ratio, covering 2 deg, 5 deg and 8 deg collective pitch settings. Dynamic wake data were taken in planes .12 and .20 radii below the rotor disk and are to be compared with analytical wake data with parameters to be identified from pitch stirring transients. The model was modified to perform such transients. The instrumentation developed for this purpose is described together with the method of data acquisition and with the test procedures. The hardware and software for several data handling systems are discussed. These systems extract from pitch stirring transients the parameters of analytical dynamic rotor wake models.
The study on utilization of advanced composites in commercial aircraft wing structures was conducted as a part of the NASA Aircraft Energy Efficiency Program to establish, by the mid-1980s, the technology for the design of a subsonic commercial transport aircraft leading to a 40% fuel savings. The study objective was to develop a plan to define the effort needed to support a production commitment for the extensive use of composite materials in wings of new generation aircraft that will enter service in the 1985-1990 time period. Identification and analysis of what was needed to meet the above plan requirements resulted in a program plan consisting of three key development areas: (1) technology development; (2) production capability development; and (3) integration and validation by designing, building, and testing major development hardware.
The development of the Shuttle Transportation System (STS) by the United States and the Spacelab pressurized modules and pallets by the European Space Agency (ESA) presents a unique multi-mission space experimentation capability to scientists and researchers of all disciplines. This capability is especially pertinent to life scientists involved in all areas of biological and behavioral research. This paper explains the solicitation, evaluation, and selection process involved in establishing life sciences experiment payloads. Explanations relative to experiment hardware development, experiment support hardware (CORE) concepts, hardware integration and test, and concepts of direct Principal Investigator involvement in the missions are presented as they are being accomplished for the first Spacelab mission. Additionally, discussions of future plans for life sciences dedicated Spacelab missions are included in an attempt to define projected capabilities for space research in the 1980s utilizing the STS.
Activities of two projects at JPL in support of DOE's Small Power Systems Program are reported. These two projects are the Point-Focusing Distributed Receiver (PFDR) Technology Project and the Point-Focusing Thermal and Electric Applications (PFTEA) Project. The PFDR Technology Project's major activity is developing the technology of solar concentrators, receivers and power conversion subsystems suitable for parabolic dish or point-focusing distributed receiver power systems. Other PFDR activities include system integration and cost estimation under mass production, as well as the testing of the hardware. The PFTEA Project's first major activity is applications analysis, that is seeking ways to introduce PFDR systems into appropriate user sectors. The second activity is systems engineering and development wherein power plant systems are analyzed for specific applications. The third activity is the installation of a series of engineering experiments in various user environments to obtain actual operating experience
Methods are defined for implementing quality assurance policy and requirements for life sciences laboratory equipment, experimental hardware, integration and test support equipment, and integrated payloads.
An experiment is planned, conducted and evaluated to determine the feasibility of using a Power Kinetics' Fresnel concentrator to provide process heat in an industrial environment. The plant provides process steam at 50 to 60 psig to two autoclaves for curing masonry blocks. When steam is not required, the plant preheats hot water for later use. A second system is installed at the Jet Propulsion Laboratory parabolic dish test site for hardware validation and experiment control. Experiment design allows for the extrapolation of results to varying demands for steam and hot water, and includes a consideration of some socio-technical factors such as the impact on production scheduling of diurnal variations in energy availability.