2,351 research outputs found
Hydrodynamic design of generic pump components
Inducer and impellar base geometries were defined for a fuel pump for a generic generator cycle. Blade surface data and inlet flowfield definition are available in sufficient detail to allow computational fluid dynamic analysis of the two components
Solar activity catalogue. Volume I - Catalogue of solar activity during 1954 - 1956
Catalog of solar activity during 1954-195
LOX/Hydrocarbon Combustion Instability Investigation
The LOX/Hydrocarbon Combustion Instability Investigation Program was structured to determine if the use of light hydrocarbon combustion fuels with liquid oxygen (LOX) produces combustion performance and stability behavior similar to the LOX/hydrogen propellant combination. In particular methane was investigated to determine if that fuel can be rated for combustion instability using the same techniques as previously used for LOX/hydrogen. These techniques included fuel temperature ramping and stability bomb tests. The hot fire program probed the combustion behavior of methane from ambient to subambient temperatures. Very interesting results were obtained from this program that have potential importance to future LOX/methane development programs. A very thorough and carefully reasoned documentation of the experimental data obtained is contained. The hot fire test logic and the associated tests are discussed. Subscale performance and stability rating testing was accomplished using 40,000 lb. thrust class hardware. Stability rating tests used both bombs and fuel temperature ramping techniques. The test program was successful in generating data for the evaluation of the methane stability characteristics relative to hydrogen and to anchor stability models. Data correlations, performance analysis, stability analyses, and key stability margin enhancement parameters are discussed
Catalogue of Solar Activity During 1958, Volume III
Solar flares, sunspots, radio emissions, solar events, geomagnetic storms, solar-terrestrial effects, and balloon flights for 195
Solar activity catalogue. Volume 4 - Catalogue of solar activity during 1959
Solar activity catalog covering solar flares, terrestrial effects, plage regions, radio emissions, geomagnetic storms, and balloon flight
Food Habits of Green Tree Frogs (Hyla cinerea) from Arkansas
We analyzed stomach contents of 120 Green Tree Frogs, Hyla cinerea, collected between May 1956 and October 2014 in Arkansas. Beetles and arachnids were the predominant prey item; the next most abundant groups were Diptera and Hemiptera. Vegetable matter was also found in several frogs. All identifiable vegetable matter was determined to be of the genus Persicaria, colloquially known as smartweed. Our data suggests that Green Tree Frogs in Arkansas predominantly feed on beetles and arachnids, but occasionally ingest plant matter when actively foraging
Radio Study of the Pulsar Wind Nebula Powered by PSR B1706-44
PSR B170644 is an energetic gamma-ray pulsar located inside supernova
remnant (SNR) G343.12.3 and it powers a compact pulsar wind nebula (PWN)
that shows torus and jet structure in X-rays. We present a radio study of the
PWN using Australia Telescope Compact Array (ATCA) observations at 3, 6, 13,
and 21\,cm. We found an overall arc-like morphology at 3 and 6\,cm, and the
``arc" shows two distinct peaks at 6\,cm. The radio emission is faint inside
the X-ray PWN and only brightens beyond that. We develop a thick torus model
with Doppler boosting effect to explain the radio PWN structure. The model
suggests a bulk flow speed of , which could indicate significant
deceleration of the flow from the X-ray emitting region. Our polarization
result reveals a highly ordered toroidal -field in the PWN. Its origin is
unclear given that the supernova reverse shock should have interacted with the
PWN. At a larger scale, the 13 and 21\,cm radio images detected a semi-circular
rim and an east-west ridge of G343.12.3. We argue that the latter could
possibly be a pulsar tail rather than a filament of the SNR, as supported by
the flat radio spectrum and the alignment between the magnetic field and its
elongation.Comment: 16 pages, 9 figures, accepted by AP
Catalogue of Solar Activity During 1960-1963, Volume V
Catalog on solar activity from 1960 to 196
An improvement in ABIC-minimizing deconvolution for continuously measured magnetic remanence data
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