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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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Gas core nuclear reactors feasibility based on gas core hydrodynamics, heat transfer and neutronics development, noting spacecraft weight and trip time reduction potential
A solution is presented for the problem of the compressive buckling of simply supported, flat, rectangular, solid-core sandwich plates stressed either in the elastic range or in the plastic range. Charts for the analysis of long sandwich plates are presented for plates having face materials of 24s-t3 aluminum alloy, 76s-t6 alclad aluminum alloy, and stainless steel. A comparison of computed and experimental buckling stresses of square solid-core sandwich plates indicates fair agreement between theory and experiment.
Stainless-steel honeycomb-core sandwich panels which differed primarily in skin thicknesses were tested at elevated temperatures under static and aerodynamic conditions. The results of these tests were evaluated to determine the insulating effectiveness and structural integrity of the panels. The static radiant-heating tests were performed in front of a quartz-tube radiant heater at panel skin temperatures up to 1,5000 F. The aerodynamic tests were made in a Mach 1.4 heated blowdown wind tunnel. The tunnel temperature was augmented by additional heat supplied by a radiant heater which raised the panel surface temperature above 8000 F during air flow. Static radiant-heating tests of 2 minutes duration showed that all the panels protected the load-carrying structure about equally well. Thin-skin panels showed an advantage for this short-time test over thick-skin panels from a standpoint of weight against insulation. Permanent inelastic strains in the form of local buckles over each cell of the honeycomb core caused an increase in surface roughness. During the aero- dynamic tests all of the panels survived with little or no damage, and panel flutter did not occur.
The results of a multigroup, diffusion theory study of spherical gaseous-core cavity reactors are presented in this report. The reactor cavity of gaseous U235 is enclosed by a region of hydrogen gas and is separated from an external D2O moderator-reflector by a zirconium structural shell. Some cylindrical reactors are also investigated. A parametric study of spherical reactors indicates that, for the range of variables studied, critical mass increases as: (1) Fuel region is compressed within the reactor cavity, (2) moderator thickness is decreased, (3) structural shell thickness is increased, and (4) moderator temperature is increased. A buckling analogy is used to estimate the critical mass of fully reflected cylindrical reactors from spherical results without fuel compression. For a reactor cavity of a 120-centimeter radius uniformly filled with fuel, no structural shell, a moderator temperature of 70 F, and a moderator thickness of 100 centimeters, the critical mass of a spherical reactor is 3.1 kilograms while that of a cylinder with a length-to-diameter ratio of 1.0 (L/D = 1) is approximately 3.8 kilograms and, with L/D = 2, 5.9 kilograms. For the range of variables considered for U235-D2O gaseous-core cavity reactors, the systems are characterized by 95 to 99 percent thermal absorptions, with the flux reaching a maximum in the moderator about 10 to 15 centimeters from the reactor cavity.
Nonuniform fluid velocity effect at surface of earth core on nature of surface flow
Forced transverse vibrations of a solid, elastic core case-bonded to an infinitely long, rigid cylinder
Controlling the frequency of a square-loop magnetic core oscillator using a dc voltage to give a voltage-to-frequency conversion for use in pulse frequency modulated telemetry systems
Square-loop cores with multiple windings used in single transformer package for application in self-oscillating inverters
Flux division in three-leg saturable ferrite core
Magnetohydrodynamics of earth core
Fuel containment and heat transfer in gaseous core fission reactors
Analytical determination of thermoconductivity of honeycomb-core panels fabricated from cobalt-base alloy
Frequency stabilized flywheel and synchronizer with magnetic core oscillator for IMP information processing system
Liquid-core reactor concept examined for nuclear rocket
Address current error detector generates signal whenever error-producing conditions arise in magnetic core arrays
Wheel-flow gaseous-core reactor concept for space vehicle propulsion
Buckling test of truss-core sandwich cylinder loaded in bending - cylinder failure due to growth of wall buckles