AERONAUTICS IN THE SPACE AGE
Aeronautics in the space age - aerodynamics - materials and structures - propulsion and energy conversion
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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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Aeronautics in the space age - aerodynamics - materials and structures - propulsion and energy conversion
Aspects of a new gaseous nuclear-rocket concept are considered. The principle of this type of cavity reactor is one of maintaining the separation of two coaxial streams - fuel within propellant - rather than attaining the separation of fuel propellant gases within the cavity. An acceptably low uranium consumption rate is possible if the fuel stream can be maintained at an axial velocity which is 1/100 to 1/1000 of the propellant velocity. An elementary hydrodynamic analysis for laminar incompressible flow indicates that the average uranium core velocity may only reach 2 to 11 times the initial core velocity for a typical reactor. The results of a 1-D criticality analysis for a D2O/(235)U system show that the effect of shrinking the fuel region within the reactor cavity is not serious; the effects of moderator heating and structural materials on critical mass are also shown. Overall rocket performance calculations are made for reasonable operating conditions; these results indicate that thrusts from 25,000 to 50,000 pounds and accelerations from 10(exp -1) to 3 g are possible.
Configurations, structures, materials, advantages and applications for parawings
Corrosion loop program to investigate structural materials and NaK coolant in SNAP-8 primary coolant circuit
Study was initiated to determine methods or test specimens for evaluating stress corrosion cracking characteristics of common structural materials. It was found that the methods of externally loading and corrosion testing were reliable in yielding reproducible results for stress corrosion evaluation.
The design, construction, and development of advanced military aircraft undoubtedly will involve the utilization of many relatively new concepts in several deafferent, but related, areas. In many cases, these new concepts will require new flight techniques or involve development problems inherent in the use of relatively unproven methods, materials, structures, systems, and configurations. Moreover, flight verification will be required of aircraft aerodynamics and flight behavior because of the usual uncertainties associated with predicted data. Solutions to these problems obviously would require flight testing involving extensive time and effort before the aircraft could become operationally acceptable. Upon the inception of the X-15 research airplane project, many new and far-reaching techniques and principles were studied and applied in the aircraft design and are currently being demonstrated and investigated. Because similar concepts are likely to be used in advanced military aircraft, the X-15 flight program will provide significant information, over a broad flight environment, pertinent to the development of these vehicles. This paper discusses the research objectives of the X-15 flight program, some of the flight aerodynamic characteristics currently being obtained, some development problems encountered, and the experience obtained with the advanced systems investigated.
Textile fabrication methods produce multidirectional materials, describing commercial use of 3-D materials
Gas pressure effects on cavitation resistance of structural materials in liquid metal space power systems
Delayed fracture in viscoelastic-plastic solids - assessment of load carrying ability of glass-like polymers having potential applications as structural materials
Adhesives, coatings, coated fabrics, elastomers, encapsulants, films, hardware and structural materials, and tapes are tested in a series of physical, mechanical, and electrical tests. Material properties are measured before and after exposure to the three environments.
Proof-load test improves statistical confidence in the estimate of reliability, numerical examples indicate a definite advantage of the proof-load approach in terms of savings in structural weight. The cost of establishing the statistical distribution of strength of the structural material is also introduced into the cost formulation
Advanced research on electronic and power systems, design criteria, and structural materials for space application
Spacecraft design for manned interplanetary missions, considering structural materials and weights, cryogenic insulation, meteoroid protection, landing gear, etc
Creep rupture effect on fatigue damage of structural material, constructing nondimensional stress range diagrams
Inert, strain sensitive tracer, cuprous oxide, added to polymeric adhesive ensures sufficiently large signal to noise ratio in NQR system output. Method is successful, provided that RF-transparent structural materials are used between modified adhesive and probe of NQR spectrometer.
Metallic composite prepared for utilization which remains intact without aluminum/carbon reactions, is less expensive than other structural materials, and yields a flexible composite material.
Reduction of overall program costs for reusable space shuttle by use of beryllium as primary structural material