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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 973 records · Page 54
All sourcesNASA NTRSDOE OSTI
NASA NTRS1975

Fracture testing with surface crack specimens

This paper is a report of ASTM Task Group E24.01.05 on Part-Through Crack Testing. It includes recommendations for the design, preparation, and static fracture testing of surface crack specimens based on the current state of the art. The recommendations are preceded by background information including discussions of stress intensity factors, crack opening displacements, and fracture toughness values associated with surface crack specimens. Cyclic-load and sustained-load tests are discussed briefly. Recommendations for further research are included.

Orange, T. W.↗
NASA NTRS1975

Fracture testing with surface crack specimens

Recommendations are given for the design, preparation, and static fracture testing of surface-crack specimens based on the current state of the art. The recommendations are preceded by background information including discussions of stress intensity factors, crack opening displacements, and fracture toughness values associated with surface-crack specimens. Cyclic-load and sustained-load tests are discussed briefly. Recommendations for further research are included.

Orange, T. W.↗
NASA NTRS1976

Space shuttle Ku-band integrated rendezvous radar/communications system study

The results are presented of work performed on the Space Shuttle Ku-Band Integrated Rendezvous Radar/Communications System Study. The recommendations and conclusions are included as well as the details explaining the results. The requirements upon which the study was based are presented along with the predicted performance of the recommended system configuration. In addition, shuttle orbiter vehicle constraints (e.g., size, weight, power, stowage space) are discussed. The tradeoffs considered and the operation of the recommended configuration are described for an optimized, integrated Ku-band radar/communications system. Basic system tradeoffs, communication design, radar design, antenna tradeoffs, antenna gimbal and drive design, antenna servo design, and deployed assembly packaging design are discussed. The communications and radar performance analyses necessary to support the system design effort are presented. Detailed derivations of the communications thermal noise error, the radar range, range rate, and angle tracking errors, and the communications transmitter distortion parameter effect on crosstalk between the unbalanced quadriphase signals are included.

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NASA NTRS1975

JANNAF Rocket Engine Performance Test Data Acquisition and Interpretation Manual

Procedures recommended by the JANNAF Performance Standardization Working Group for acquisition and Interpretation of performance test data are presented. Included with the description of these procedures are recommended procedures covering the required measurements, associated instrumentation, calibration methods, and data uncertainties. In addition, criteria for the applicability of existing test data, the selection of test models, and analytical performance prediction improvement based on test results are outlined. Three sample cases using the recommended procedures are presented as an addendum under separate cover. Author

Evans, S. A.↗
NASA NTRS1978

Definition of air quality measurements for monitoring space shuttle launches

A description of a recommended air quality monitoring network to characterize the impact on ambient air quality in the Kennedy Space Center (KSC) (area) of space shuttle launch operations is given. Analysis of ground cloud processes and prevalent meteorological conditions indicates that transient HCl depositions can be a cause for concern. The system designed to monitor HCl employs an extensive network of inexpensive detectors combined with a central analysis device. An acid rain network is also recommended. A quantitative measure of projected minimal long-term impact involves the limited monitoring of NOx and particulates. All recommended monitoring is confined ti KSC property.

Thorpe, R. D.↗
NASA NTRS1979

The kW power module evolution study: Executive summary

Using the Marshall Space Flight Center 25 kW Power Module (PM) reference design as a point of departure, the study defined evolutionary growth paths to 100 kW and above. A recommended development approach and initial configurations were described. Specific hardware changes from the reference design are recommended for the initial PM configuration to ensure evolutionary growth, improved replicability, and reduced cost. Certain functional changes are also recommended to enhance system capabilities.

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NASA NTRS1978

Satellite Power System (SPS) student participation

A assessment of methods which are appropriate to initiate student participation in the discussion of a satellite power system (SPS) is presented. Methods which are incorporated into the campus environment and the on-going learning experience are reported. The discussion of individual methods for student participation includes a description of the technique, followed by comments on its enhancing and limiting factors, references to situations where the method has been demonstrated, and a brief consideration of cost factors. The two categories of recommendations presented are: an outline of fourteen recommendations addressing specific activities related to student participation in the discussion of SPS, and three recommendations pertaining to student participation activities in general.

Ladwig, A.↗
NASA NTRS1979

The Solar Power Satellite concept - Towards the future

An evolutionary program phasing with respect to the development of a Solar Power Satellite (SPS) is considered, taking into account concept identification, concept evaluation, exploratory research, space technology projects, system development, and commercial operations. At the present time the concept evaluation phase of the program is underway. This phase is scheduled for completion in 1980. It will result in a recommendation as to whether the concept should be explored further and if so, in what manner. The recommendation will be based on technical feasibility, economic and environmental considerations, and comparisons with other potential systems of the future. It is premature to speculate on the conclusions and recommendations from the evaluation program as to whether the program should proceed to the next phase.

Kraft, C. C., Jr.↗
NASA NTRS1976

Flight service evaluation of an advanced composite empennage component on commercial transport aircraft

The development and flight evaluation of an advanced composite empennage component is presented. The recommended concept for the covers is graphite-epoxy hats bonded to a graphite-epoxy skin. The hat flare-out has been eliminated, instead the hat is continuous into the joint. The recommended concept for the spars is graphite-epoxy caps and a hybrid of Kevlar-49 and graphite-epoxy in the spar web. The spar cap, spar web stiffeners for attaching the ribs, and intermediate stiffeners are planned to be fabricated as a unit. Access hole in the web will be reinforced with a donut type, zero degree graphite-epoxy wound reinforcement. The miniwich design concept in the upper three ribs originally proposed is changed to a graphite-epoxy stiffened solid laminate design concept. The recommended configuration for the lower seven ribs remains as graphite-epoxy caps with aluminum cruciform diagonals. The indicated weight saving for the current advanced composite vertical fin configuration is 20.2% including a 24 lb growth allowance. The project production cost saving is approximately 1% based on a cumulative average of 250 aircraft and including only material, production labor, and quality assurance costs.

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NASA NTRS1980

Upgrading the free flying rendezvous and docking simulator and the orbital servicer system

Recommendations are made for upgrading two teleoperator/robotics test and simulation systems based upon a review of latest technology advances in the involved disciplines. A second generation Free Flying Mobility Unit is recommended which adds a sixth degree of freedom and incorporates other improvements which greatly expand the center's capability to perform evaluation tests and demonstrations of advanced systems concepts for rendezvous and docking in support of the Teleoperator Maneuvering System (TMS) Program. The Orbital Servicer System provides the capability for testing and demonstrating concepts for on orbit servicing of compatibly designed satellites/payloads. The TMS is to be the transporting vehicle for the servicer. The manipulator arm of the Orbital service System is presently computer controlled in the trajectory portion of the module transfer operation. The ultimate objective is to fully automte its operation requiring additional capabilities in sensors, artificial intelligence, image analysis, communications, computer programming, pattern recognition, kinematics, and manipulator design. It is recommended that the Electronics and Control Laboratory move to acquire the basic competencies in robotics necessary to achieve full automation.

Eastman, R. M.↗
NASA NTRS1980

An evaluation of NASA's program for improving aircraft fuel efficiency

The report provides commentary and recommendations where appropriate on each of the major elements of the program. Key findings of the committee included a recommendation that closer ties be established between NASA and the FAA to expedite the use and acceptance of the new technology. The committee also cited the potential for fuel savings through an imporved air traffic control system and recommended that the management of NASA and the FAA discuss ways and means to work together to exploit more effectively the capabilities and responsibilities of each to develop air traffic control.

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NASA NTRS1980

Summary of flight technology workshop on radiometric calibration

The conclusions and recommendations from a three-day NASA sponsored workshop to assess deficiencies and shortcomings of previously flown electro-optical space sensors are summarized. Space technologists for NASA, NOAA, DOD, and industry also developed recommendations for improving instrumentation and calibration technology. The conclusions reached include the fact that the past knowledge of in-orbit radiometric accuracy has been poor relative to available calibration standards, whereas stringent accuracy requirements for planned NASA programs will require significant SOA improvements. The Shuttle contamination environment may also compromise future sensor accuracy. A number of panel recommendations to improve in-orbit accuracy of future sensors will be summarized, including one to establish a set of National Standards for Remote Sensors at NBS as a basis for long term accuracy.

Dodgen, J. A.↗
NASA NTRS1982

Role of passive remote sensors. Sensor System Panel report

Capabilities of present passive systems are described and the development of passive remote sensing systems for the more abundant tropospheric trace species is recommended. The combination of nadir-viewing spectrometers and solar occultation for tropospheric measurement of those gases having large stratospheric burdens is discussed. Development of a nadir-viewing instrument capable of obtaining continuous spectra in narrower bands is recommended. Gas filter radiometers for species specific measurements and development of a spectral survey instrument are discussed. Further development of aerosol retrieval algorithms, including polarization techniques, for obtaining aerosol thickness and size distributions is advised. Recommendations of specific investigations to be pursued are presented.

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NASA NTRS1982

Sulfur-dioxide/water equilibria between 0 and 50 C - An examination of data at low concentrations

In order to resolve the discrepancy noted in values currently used for the first dissociation constant of SO2 in water, the pertinent literature was critically examined and a value of 0.0132 M at 25 C was recommended. An expression correlating this value as a function of temperature for zero-50 C has been developed. Attention is also given to the literature for the Henry's law constant, and a value of 1.242 M/atm at 25 C is recommended. Ionic activity corrections and speciation in more concentrated solutions are discussed, and recommendations are made for estimating the activity coefficients of the various ionic species in solutions of moderate ionic strength.

Maahs, H. G.↗
NASA NTRS1983

A program for planetary exploration

A series of recommendations constituting a core program for planetary exploration, to last from the present to the year 2000, is the outcome of a two-year study undertaken by the NASA Solar System Exploration Committee. The missions envisioned by the core program must be insulated from costly changes and delays once they are approved. The present Committee has therefore restricted its recommendations to missions which do not require novel technologies, but rather continue the techniques of the flybys, orbiters and atmospheric entry probes that have been successful in the past. Recommendations are made for exploration of the inner planets, cometary and asteroid bodies, and the outer planets. Attention is given to the identification of key elements driving mission costs. It is noted that the Space Shuttle/Centaur upper stage combination brings within reach comet and asteroid rendezvous missions that were once thought to require costly new technology.

Morrison, D.↗
NASA NTRS1983

Terrestrial whisker growth experiments which anticipate some special effects of a space station environment

The effects of the absence of gravitationally driven thermal convection on the growth of whiskers by chemical reduction of metal salts was studied. It was possible to accomplish nearly complete suppression of such convection. Suppression of the convection does indeed effect the growth but in subtle, not necessarily detrimental ways: none of the changes observed were such as to hamper efforts to produce whiskers in space. Copper whiskers grown from cuprous iodide respond most positively to the suppression of convection; therefore, they are strongly recommended for tests in the space environment. Cobalt whiskers grown from cobaltous bromide show the greatest independence from conditions of convection and applied electric fields of any material studied; therefore, this medium is highly recommended. A strong pulse of electric field forces the whiskers to stick to the growth vessel top plate, this facilitates study or "harvesting'. On the space station it is recommended that the growth vessels be mounted outside the laboratory and joined with the station by means of double vacuum valves and gas service lines.

Hobbs, H. H.↗
NASA NTRS1983

Cogeneration computer model assessment: Advanced cogeneration research study

Cogeneration computer simulation models to recommend the most desirable models or their components for use by the Southern California Edison Company (SCE) in evaluating potential cogeneration projects was assessed. Existing cogeneration modeling capabilities are described, preferred models are identified, and an approach to the development of a code which will best satisfy SCE requirements is recommended. Five models (CELCAP, COGEN 2, CPA, DEUS, and OASIS) are recommended for further consideration.

Rosenberg, L.↗
NASA NTRS1983

Role of theory in space science

The goal of theory is to understand how the fundamental laws of physics laws of physics and chemistry give rise to the features of the universe. It is recommended that NASA establish independent theoretical research programs in planetary sciences and in astrophysics similar to the solar-system plasma-physics theory program, which is characterized by stable, long-term support for theorists in university departments, NASA centers, and other organizations engaged in research in topics relevant to present and future space-derived data. It is recommended that NASA keep these programs under review to full benefit from the resulting research and to assure opportunities for inflow of new ideas and investigators. Also, provisions should be made by NASA for the computing needs of the theorists in the programs. Finally, it is recommended that NASA involve knowledgeable theorists in mission planning activities at all levels, from the formulation of long-term scientific strategies through the planning and operation of specific missions.

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