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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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All sourcesNASA NTRSDOE OSTI
NASA NTRS1979

Investigation of the asymmetric aerodynamic characteristics of cylindrical bodies of revolution with variations in nose geometry and rotational orientation at angles of attack to 58 degrees and Mach numbers to 2

Wind-tunnel tests were conducted to investigate the side forces and yawing moments that can occur at high angles of attack and zero sideslip for cylindrical bodies of revolution. Two bodies having several tangent ogive forebodies with fineness ratios of 0.5, 1.5, 2.5, and 3.5 were tested. The forebodies with fineness ratios of 2.5 and 3.5 had several bluntnesses. The cylindrical afterbodies had fineness ratios of 7 and 13. The model components - tip, forebody, and afterbody - were tested in various rotational positions about their axes of symmetry. Most of the tests were conducted at a Mach number of 0.25, a Reynolds number of 0.32 x 10 to the 6th power, and with the afterbody that had a fineness ratio of 7 and with selected forebodies. The effect of Mach number was determined with the afterbody that had a fineness ratio of 13 and with selected forebodies at mach numbers from 0.25 to 2 at Reynolds number = 0.32 X 10 to the 6th power. Maximum angle of attack was 58 deg.

Kruse, R. L.↗
NASA NTRS1980

Soft X-ray observations of the supernova remnants HB 3 and 3C 58

The HEAO 1 A-2 low energy detectors have discovered soft X-ray emission from a source positionally coincident with the supernova remnant HB 3. The flux in the energy range 0.3-2.2 keV is about 6 x 10 to the -11th ergs per sq cm s. The spectral data are fitted to a hydrogen thermal bremsstrahlung model, and the physical parameters of the supernova remnant are estimated. The age derived is about 21,000 years, and the initial blast energy is about 3.1 x 10 to the 50th ergs. Upper limits to the soft X-ray flux and the luminosity of the supernova remnant 3 C 58 are also derived.

Galas, C. M. F.↗
NASA NTRS1986

Summary of a high subsonic force/pressure experiment for 58 deg cambered/twisted thick delta wings

This paper summarizes the results of a force, moment, and pressure experiment involving six thick, cambered and twisted, delta wings with 58 deg leading-edge sweep. This experiment was conducted in the NASA Langley 7- by 10-foot High-Speed Tunnel at Mach numbers of 0.75, 0.80, and 0.83. The design goal was a configuration which was self-trimming at a lift coefficient of 0.25 and Mach number of 0.80. Although the design goal was not met, the configuration which came closest and which had the best overall performance was selected for further study. Wing surface pressure data and limited surface oil flow data for this configuration are presented to show the extent of attached flow at the design point. For selected cases, inviscid solutions from vortex lattice method/suction analogy, PAN AIR, FLO-28, and FLO-57 are compared with the experimental force, moment, and pressure data.

Chu, J.↗
NASA NTRS1989

Climatology and trends of mesospheric (58-90) temperatures based upon 1982-1986 SME limb scattering profiles

Atmospheric temperature profiles for the altitude range 58-90 km were calculated using data on global UV limb radiances from the SME satellite. The major elements of this climatology include a high vertical resolution (about 4 km) and the coverage of the 70-90 km altitude region. The analysis of this extensive data set provides a global definition of mesospheric-lower thermospheric temperature trends over the 1982-1986 period. The observations suggest a pattern of 1-2 K/year decreases in temperatures at 80-90-km altitudes accompanied by 0.5-1.5 K/year increases in temperatures at 65-80-km altitudes.

Clancy, R. Todd↗
NASA NTRS1989

A 58 x 62 pixel Si:Ga array camera for 5 - 14 micron astronomical imaging

A new infrared array camera system has been successfully applied to high background 5 - 14 micron astronomical imaging photometry observations, using a hybrid 58 x 62 pixel Si:Ga array detector. The off-axis reflective optical design incorporating a parabolic camera mirror, circular variable filter wheel, and cold aperture stop produces diffraction-limited images with negligible spatial distortion and minimum thermal background loading. The camera electronic system architecture is divided into three subsystems: (1) high-speed analog front end, including 2-channel preamp module, array address timing generator, bias power suppies, (2) two 16 bit, 3 microsec per conversion A/D converters interfaced to an arithmetic array processor, and (3) an LSI 11/73 camera control and data analysis computer. The background-limited observational noise performance of the camera at the NASA/IRTF telescope is NEFD (1 sigma) = 0.05 Jy/pixel min exp 1/2.

Gezari, D. Y.↗
NASA NTRS1923

New Albatross commercial airplane "L 58"

The "L 58" is a monoplane with cantilever wings joined directly to the fuselage. It accordingly belongs to the new school of airplane construction, as founded and developed in Germany. A list of performance characteristics is included.

Meyer, G↗
NASA NTRS1994

The OB association LH 58 in the Large Magellanic Cloud

We present charge coupled device (CCD) photometry and spectroscopy for stars in Lucke-Hodge 58, an isolated OB association in the Large Magellanic Cloud (LMC) northwest of 30 Doradus. The photometric catalog contains 839 stars with UBV magnitudes complete to V approximately = 19. We have obtained spectra and classified 35 stars; combined with previous published spectral types, we find 22 O-type stars. The earliest type is O3-4 V, and there are three Wolf-Rayet (WR) stars in the association. The slope of the initial mass function, Gamma = -1.7 +/- 0.3, is in good agreement with other LMC associations. The presence of several evolved supergiants with masses about 15-25 solar mass suggests that some star formation took place as early as 10 million years ago, but the majority of stars formed coevally within the past few million years.

Garmany, Catharine D.↗
NASA NTRS2021

A Weakening Compton Hump and Soft X-ray Excess Detected in the Seyfert-1 Galaxy MCG –02–58–22

We have carried out an extensive X-ray spectral study of the bare Seyfert-1 galaxy MCG –02–58–22to ascertain the nature of the X-ray reprocessing media, using observations from Suzaku(2009) and simultaneous observations from XMM-Newton and NuSTAR(2016) . The most significant results of our investigation are: 1. The primary X-ray emission from the corona is constant in these observations, both in terms of the power law slope (Γ = 1.80) and luminosity (L2−10 keV= 2.55×1044erg s−1). 2.The soft excess flux decreased by a factor of two in 2016, the Compton hump weakened/vanished in2016, and the narrow FeKαemission line became marginally broad (σ= 0.35±0.08 keV) and its flux doubled in 2016. 3. From physical model fits we find that the normalization of the narrow component of the FeKαline does not change in the two epochs, although the Compton hump vanishes in the same time span. Since the primary X-ray continuum does not change, we presume that any changes in there processed emission must arise due to changes in the reprocessing media. Our primary conclusions are: A. The vanishing of the Compton hump in 2016 can probably be explained by a dynamic clumpytorus which is infalling/outflowing, or by a polar torus wind. B. The torus in this AGN possibly has two structures: an equatorial toroidal disk (producing the narrow FeKαemission) and a polar component(producing the variable Compton hump), C. The reduction of the soft-excess flux by half and increase in the FeKαflux by a factor of two in the same period cannot be adequately explained by ionized disk reflection model alone.

Sibasish Laha↗
NASA NTRS1974

Experimental aerodynamic characteristics for a cylindrical body of revolution with various noses at angles of attack from 0 deg to 58 deg and Mach numbers from 0.6 to 2.0

An experimental investigation was conducted to determine the effect of forebody geometry, a grit ring around the nose, Reynolds number, Mach number, and angle of attack on the aerodynamic characteristics of a body of revolution. Aerodynamic force and moment characteristics were measured for a cylindrical body with tangent ogive noses of fineness ratio 2.5, 3.0, 3.5, and 5.0. The cylindrical body was tested with an ogive nose having a rounded tip and an ogive nose with two different nose strake arrangements. Aerodynamic configurations were tested at various Mach numbers, angles of attack, and Reynolds numbers. The data demonstrate that the aerodynamic characteristics for a body of revolution can be significantly affected by changes in nose fineness ratio, nose bluntness, Reynolds number, Mach number, and, of course, angle of attack. Nose strakes increased the normal forces but had little effect on the side forces that developed at subsonic Mach numbers for alpha greater than about 25. A grit ring around the nose had little or no effect on the aerodynamic characteristics.

Jorgensen, L. H.↗
NASA NTRS1975

Experimental aerodynamic characteristics for a cylindrical body of revolution with side strakes and various noses at angles of attack from 0 degrees to 58 degrees and Mach numbers from 0.6 to 2.0

For a body of revolution with afterbody side strakes, an experimental investigation was conducted in the Ames 6- by 6-Foot Wind Tunnel to determine the effects on the aerodynamic characteristics of forebody geometry, nose strakes, body side strakes, Reynolds number, Mach number, and angle of attack. Aerodynamic force and moment characteristics were measured for the straked cylindrical afterbody (cylinder fineness ratio of 7) with tangent ogive noses of fineness ratio 2.5 to 5.0. In addition, the straked cylinder afterbody was tested with an ogive nose having a rounded tip and an ogive nose with two different nose strake arrangements. The data demonstrate that the aerodynamic characteristics for a body of revolution with side strakes can be significantly affected by changes in nose fineness ratio, nose bluntness, Reynolds number, Mach number, and, of course, angle of attack. Removing the strakes from the cylindrical aftersection greatly decreased the lift, but this removal hardly changed the maximum magnitudes of the undesirable side forces that developed at angles of attack greater than about 25 deg for subsonic Mach numbers.

Jorgensen, L. H.↗
NASA NTRS1980

A temperature fixed point near 58 C

Triple-point cell contrains about 300 g of high-purity succinontrile. Experiments show that lower 4 cm of thermometer well are virtually isothermal, making placement of thermometer not very critical. Bulb at bottom of well helps to prevent solid succinontrile mantel from slipping.

Glicksman, M. E.↗