Showing papers on "Shields published in 1982"
TL;DR: In this paper, a new analysis for designing dual-layer shields is presented which is based on energy and momentum conservation, fundamental electromagnetic radiation physics, and the observation of results of extensive experimental impact studies performed at relatively low velocities (near 7 km/s).
24 citations
TL;DR: In this paper, the authors used a sodium iodide spectrometer for penetration through shields in six possible two-layer combinations of aluminium, steel and lead, and found that the exposure build-up factor was higher than predicted for aluminium only shields.
5 citations
TL;DR: In this article, a set of five concentric cylindrical magnetic shields made of Moly Permalloy was used for the case of the hydrogen maser and it was found that the longitudinal and transverse shielding factors were respectively 100 and 125 dB.
Abstract: A set of five concentric cylindrical magnetic shields made of Moly Permalloy is studied. The results obtained are applied to the case of the hydrogen maser. It is found that the longitudinal and transverse shielding factors are respectively 100 and 125 dB. The improvement over the more standard three shields approach is 33 dB for the longitudinal shielding factor and 40 dB for the transverse shielding factor.
4 citations
01 Jan 1982
3 citations
01 Jun 1982
TL;DR: A preliminary design of the thermal protection system for the NASA Solar Probe spacecraft is presented in this paper, which satisfies maximum envelope, structural integrity, equipotential, and mass loss/contamination requirements by employing lightweight carbon-carbon emissive shields.
Abstract: A preliminary design of the thermal protection system for the NASA Solar Probe spacecraft is presented. As presently conceived, the spacecraft will be launched by the Space Shuttle on a Jovian swing-by trajectory and at perihelion approach to three solar radii of the surface of the Earth's sun. The system design satisfies maximum envelope, structural integrity, equipotential, and mass loss/contamination requirements by employing lightweight carbon-carbon emissive shields. The primary shield is a thin shell, 15.5-deg half-angle cone which absorbs direct solar flux at up to 10-deg off-nadir spacecraft pointing angles. Secondary shields of sandwich construction and low thickness-direction thermal conductivity are used to reduce the primary shield infrared radiation to the spacecraft payload.
3 citations
TL;DR: In this article, the authors made measurements of emerging γ fluxes for 6.2 MeV source photons, from a large diameter disc radiator, penetrating concrete shields with and without double right-angled ducts.
3 citations
Dissertation•
01 May 1982
2 citations
1 citations
TL;DR: In this article, an analysis of the transfer admittance-coupled response of an electrical cable bundle exposed to nuclear x-rays is presented, in which the electric field induced by SGEMP between the outer and inner shields couples to the wires via small apertures in the inner shields.
Abstract: One of the ways energy can couple to the inner wires of an electrical cable bundle exposed to nuclear x-rays involves the transfer admittance of the inner bundle shields; we present an analysis of this coupling mode, in which the electric field induced by SGEMP between the outer and inner shields couples to the wires via small apertures in the inner shields. Using an equivalent circuit model, the transfer admittance-coupled response is calculated for a generic cable bundle, and compared with the direct injection response. Sensitivity of the response to significant cable parameters is investigated, and limitations of the model are discussed. It is shown that an insulating tape wrap adjacent to the outer shield, often present as a fabrication aid, reduces the response by about an order of magnitude.
1 citations
Patent•
02 Dec 1982
TL;DR: In this article, a coke oven door is constructed from a plurality of slightly overlapping shields, the individual shields being held by means of spacers which at the same time serve for fixing an insulating layer located on the inside of the door body.
Abstract: Coke oven doors serve to seal the horizontal-chamber coke ovens and consist, in addition to the door body, of a coking plate which is arranged at a distance from the door body and is assembled from a plurality of slightly overlapping shields, the individual shields being held by means of spacers which at the same time serve for fixing an insulating layer located on the inside of the door body. The individual shields have, on the underside, reinforcing ribs which serve for joining to the spacers holding the shields only at one top side, while they each loosely rest with the other top side on the next shield. This forms a kind of scale armour which has an approximately flat surface towards the coke cake bearing on it and can be easily assembled and dismantled. The coking plate consisting of individual shields serves at the same time for heating the top parts of the coke cake, which considerably contributes to an improvement in the quality thereof.
01 Jan 1982
TL;DR: In this paper, a multishielded Dewar was constructed and tested at nitrogen and helium temperatures, achieving evaporation rates of 5.6 and 3.0 liquid cm3 per hour for liquid helium and nitrogen, respectively.
Abstract: We have constructed a multishielded Dewar which we have tested at nitrogen and helium temperatures. The Dewar is of extremely simple design, requires no special insulating materials, and attains excellent performance. With an arrangement of 20 shields we have obtained evaporation rates of 5.6 and 3.0 liquid cm3 per hour for liquid helium and nitrogen, respectively. We report measurements of temperature distributions and evaporation rate as a function of the number of shields.
TL;DR: In this paper, the authors describe a shield to guard a dc superconducting field from an ac field, which is similar to the one we use in this paper, but different in many respects.