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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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Acoustical tests of full scale fans for jet engines are presented. The fans are described and some aerodynamic operating data are given. Far field noise around the fan was measured for a variety of configurations over a range of operating conditions. Complete results of one third octave band analysis are presented in tabular form. Power spectra and sideline perceived noise levels are included.
Meteorological soundings of the upper stratosphere and mesosphere, conducted with in situ rocket techniques during all seasons of the year from several sites, ranging in latitude from 8 deg S to 71 deg N, are analyzed. The resulting data are compiled into mean monthly and seasonal profiles of temperature, pressure, density, and wind for each site and are presented in graphical and tabular form. Analyses of these mean values produced time cross sections, quasi-meridional cross sections, and constant level maps which are included.
The technical and analytical support used to aid in developing requirements for planetary quarantine are presented. The investigation was divided into 8 work tasks which are presented in tabular form. Data include methods of sterilization, safety margins for quarantine, revision of contamination logs for Mars and Venus, and estimates of encapsulated and 'free' microbial burden.
A computer program for determining the partial pressures of various gases from residual-gas-analyzer data is given. The analysis of the ion currents of 18 m/e spectrometer peaks allows the determination of 12 gases simultaneously. Comparison is made to ion-gage readings along with certain other control information. The output data are presented in both tabular and graphical form.
Limited data on the bursting of circular, initially flat, grooved and plain steel diaphragms opening into a 30.5-cm-square section are presented in tabular form. In addition, these data were used to determine values of an empirical constant to be used in a design equation for predicting diaphragm bursting pressures and opening times.
The SRM booster stage program cost estimate and time-phased funding requirements are presented in tabular form. Graphs on parametric analysis are also considered.
Details of the test program, an outline of the test procedure, and results of the investigation in tabular form are presented. The base drag reduction potential was determined at cruise conditions (M = .40) of a modified base region, with and without base bleed flow. Transonic effects and cruise control effectiveness of the new base region were also obtained. The tests were performed at Mach numbers from 0.40 to 1.10, at angles of attack from -4 to +20 degrees and at angles of sideslip from -6 to +6 degrees, all at a Reynolds number of 6.56 million per meter (2.0 million per foot).
An explicit numerical solution of the compressible Navier-Stokes equations is applied to the thermodynamic analysis of supercritical oxygen in the Apollo cryogenic storage system. The wave character is retained in the conservation equations which are written in the basic fluid variables for a two-dimensional Cartesian coordinate system. Control-volume cells are employed to simplify imposition of boundary conditions and to ensure strict observance of local and global conservation principles. Non-linear real-gas thermodynamic properties responsible for the pressure collapse phenomonon in supercritical fluids are represented by tabular and empirical functions relating pressure and temperature to density and internal energy. Wall boundary conditions are adjusted at one cell face to emit a prescribed mass flowrate. Scaling principles are invoked to achieve acceptable computer execution times for very low Mach number convection problems. Detailed simulations of thermal stratification and fluid mixing occurring under low acceleration in the Apollo 12 supercritical oxygen tank are presented which model the pressure decay associated with de-stratification induced by an ordinary vehicle maneuver and heater cycle operation.
An experimental wind-tunnel investigation to determine the aerodynamic interference and the jet-wake interference associated with the wing, pylon, and high-bypass-ratio, powered, fan-jet model engines has been conducted on a typical high-wing logistics transport airplane configuration. Pressures were measured on the wing and pylons and on the surfaces of the engine fan cowl, turbine cowl, and plug. Combinations of wing, pylons, engines, and flow-through nacelles were tested, and the pressure coefficients are presented in tabular form. Tests were conducted at Mach numbers from 0.700 to 0.825 and angles of attack from -2 to 4 deg.
The major sources of neutrons from plutonium dioxide nuclear fuel are considered in detail. These sources include spontaneous fission of several of the Pu isotopes, (alpha, n) reactions with low Z impurities in the fuel, and (alpha, n) reactions with O-18. For spontaneous fission neutrons a value of (1.95 + or - 0.07) X 1,000 n/s/g PuO2 is obtained. The neutron yield from (alpha, n) reactions with oxygen is calculated by integrating the reaction rate equation over all alpha-particle energies and all center-of-mass angles. The results indicate a neutron emission rate of (1.14 + or - 0.26) X 10,000 n/s/g PuO2. The neutron yield from (alpha, n) reactions with low Z impurities in the fuel is presented in tabular form for one part part per million of each impurity. The total neutron yield due to the combined effects of all the impurities depends upon the fractional weight concentration of each impurity. The total neutron flux emitted from a particular fuel geometry is estimated by adding the neutron yield due to the induced fission to the other neutron sources.
An axisymmetric nozzle has been designed to produce test section flow at a Mach number of 8.0 for use in a hypersonic test facility at MSFC. Nominal design conditions used to calculate the viscous correction to the wall contour were selected from the results of a parametric boundary layer investigation so that the widest possible range of satisfactory operating conditions could be obtained. Coordinates for the nozzle are presented in a tabular form suitable for design and manufacturing. The basic analysis techniques have been used to generate results to compare with experimental data from a facility at Langley Research Center. The agreement was reasonably good.
A computer program is presented by which the effects of nonlinear suspension-system elastic characteristics on parachute inflation loads and motions can be investigated. A mathematical elastic model of suspension-system geometry is coupled to the planar equations of motion of a general vehicle and canopy. Canopy geometry and aerodynamic drag characteristics and suspension-system elastic properties are tabular inputs. The equations of motion are numerically integrated by use of an equivalent fifth-order Runge-Kutta technique.
The development of thermal control systems with high reliability and long service life is discussed. Various passive and semi-active thermal control systems which have been installed on space vehicles are described. The properties of the various coatings are presented in tabular form.
Optical depths of the interstellar and intergalactic media for supernova remnants, stars, and galaxies are presented in tabular form.
Updated radiation data were obtained for the UK-4 satellite by performing orbital flux integrations for protons and electrons along a specified flight path, using current field and environment models. In this process, adjustments were made to the electron data to account for temporal variations. The final results are presented in tabular and graphical form.
An experimental program was undertaken to determine the pressure distribution induced on aerodynamic bodies by a subsonic cold jet exhausting normal to the body surface and into a subsonic free stream. The investigation was limited to two bodies with single exhaust jets a flat plate at zero angle of attack with respect to the free-stream flow and a cylinder, fitted with a conical nose, with the longitudinal axis alined with the free-stream flow. Experimental data were obtained for free-stream velocity to jet velocity ratios between 0.3 and 0.5. The experimental data are presented in tabular form with appropriate graphs to indicate pressure coefficient contours, pressure coefficient decay, pitching-moment characteristics, and lift characteristics.
A method of parameter extraction for stability and control derivatives of aircraft from flight test data, implementing maximum likelihood estimation, has been developed and successfully applied to actual lateral flight test data from a modern sophisticated jet fighter. This application demonstrates the important role played by the analyst in combining engineering judgment and estimator statistics to yield meaningful results. During the analysis, the problems of uniqueness of the extracted set of parameters and of longitudinal coupling effects were encountered and resolved. The results for all flight runs are presented in tabular form and as time history comparisons between the estimated states and the actual flight test data.
After 7.5 years of storage at ambient temperature, a solid propellant apogee motor was tested successfully. The performance of the motor did not deteriorate as a result of prolonged storage. Tabular performance data and graphic thrust and pressure variations are given.