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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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Integrated experiment package to measure lunar surface composition - gamma ray, alpha particle, X ray fluorescence, and neutron albedo experiments
Q switched lasers for obtaining clear surfaces in vacuum
High temperature heat treatment effects on Mo, W, Ta and Re crystal surface order and faceting observed by electron diffraction, noting contamination role
Radiatively interacting adjoint plates in presence of collimated solar flux, considering surface roughness effects on equilibrium temperature distribution
Fluid conductivity of lunar surface materials
Influence of surface films on plastic deformation of zinc single crystals during sliding
Radiatively interacting adjoint plates in presence of collimated solar flux, considering surface roughness effects on equilibrium temperature distribution
Surface state energy positions determination in high-energy gap semiconductors by photovoltage spectral distribution
Surface oxide, organic and lead film effects on friction and plastic deformation of Zn single crystal during sliding
Permeability probe for measuring fluid flow through porous lunar surface materials
A magnetic hysteresis classification of the lunar surface is presented. It was found that there is a distinct correlation between natural remanence (NRM), saturation magnetization, and the hysteresis ratios for the rock samples. The hysteresis classification is able to explain some aspects of time dependent magnetization in the lunar samples and relates the initial susceptibility to NRM, viscous remanence, and to other aspects of magnetization in lunar samples. It is also considered that since up to 60% of the iron in the lunar soil may be super paramagnetic at 400 K, and only 10% at 100 K, the 50% which becomes ferromagnetic over the cycle has the characteristics of thermoremanence and may provide for an enhancement in measurable field on the dark side during a subsatellite magnetometer circuit.
The program was designed to provide solutions of engineering accuracy for determining the aerodynamic loads on single- or multiple-lifting-surface configurations that represent vehicles in subsonic flight, e.g., wings, wing-tail, wing-canard, lifting bodies, etc. The preparation is described of the input data, associated input arrangement, and the output format for the program data, including specification of the various operational details of the program such as array sizes, tape numbers utilized, and program dumps. A full description of the underlying theory used in the program development and a review of the program qualification tests are included.
SEASAT instrumentation payload requirements to provide satellite data for the Navy fleet operational fog prediction program include: (1) some form of C-band microwave radiometer capability; (2) a scanning antenna with a 40-km Instanteneous Field of View (IFOV) for the C-band channel; (3) a narrow band and high resolution IR scanning radiometer for cloud free areas; and (4) a capability for measuring surface winds of 3 to 50 m/sec at + or - 10% accuracy and 50 to 100 km spatial resolution.
Eolian erosion and deposition on earth was studied in order to interpret the eolian land forms of Mars. Emphasis of the wind tunnel studies was on the flow field around models of eolian forms. Areas of the wind tunnel studies include: simulation of the atmospheric boundary layer; velocity profile measurements around different models in the desert boundary layer, and estimating shear stress distributions on the model surfaces; flow visualization techniques; streamline mapping using tuft photographs; and roughness contrasts.
Wind tunnel tests have been made to investigate the possibility of reducing the hinge moments of a control surface by beveling the trailing edge. The tests were made with a 9 percent thick airfoil having a 30 percent chord plain flap. A faired beveled shape, 5 percent of the airfoil chord in width and having a thickness of 21/2 percent of the airfoil chord, was found to give approximately 50 percent reduction in the hinge moment caused by a given deflection of the flap and 80 percent reduction in the hinge moment due to the angle of attack of this airfoil for a wide range of angles. Elliptical trailing edge shapes were also tried but were found to be somewhat less effective.
A method for the construction of color variations and surface brightness across a galactic spiral arm, using the concepts and results of the density-wave theory, is developed. The color variation measured by the index Q varies with the ratio of the light of young stars to that of the old stars, the initial mass function, and the pattern speed. The fact that the variation of brightness and color across a spiral arm is relatively smooth and symmetrical and not sharp as in the galactic shock picture is due to the smearing-out effects of star formation inside a cloud in the regions behind the galactic shock, and the tendency of new stars to fall back to small galactocentric distances after their formation because of their lower angular velocity at birth. Both effects arise naturally in the context of the density-wave theory.
The turbulent boundary layer over three porous walls with different surface geometries was studied in order to investigate the individual influences of porosity and small roughness, as well as their combined effects, on turbulent boundary layer behavior. The tests were conducted in a 2 m x 2 m tunnel on a large axisymmetric model at speeds corresponding to Re(L) = 5,000,000-6,000,000. The development of the turbulent boundary layer was compared for that of sintered metal, bonded screening, and perforated sheet and then to that for the flow over a solid smooth wall and a solid, sand-roughened wall. The comparisons reveal that the effect of porosity is to shift the logarithmic region of the wall law down by a certain amount from the solid wall results and to increase the skin friction values by about 30-40%. The downward shift of the logarithmic region of the wall law and the increase of the skin friction value by the combined effects of small roughness and porosity are found to be roughly the sum of their individual effects.
Substrates to be contaminated and contamination source were prepared. Additional information on paint spray method apparatus was obtained. Silver teflon second surface mirror samples and S 13 GLO paint samples were mounted, photographed under the microscope and measured to establish baseline data. Atomic oxygen cleaning and spray painting are being considered. Electrostatic powder and plasma spray coating systems appear to have serious drawbacks.