Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “YAsS”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

7 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on YAsSe by Materials Project

YAsSe crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Y3+ is bonded in a 9-coordinate geometry to four equivalent As1- and five equivalent Se2- atoms. There are a spread of Y–As bond distances ranging from 3.07–3.20 Å. There are a spread of Y–Se bond distances ranging from 2.90–3.06 Å. As1- is bonded in a 8-coordinate geometry to four equivalent Y3+ and four equivalent As1- atoms. There are a spread of As–As bond distances ranging from 2.57–3.00 Å. Se2- is bonded in a 5-coordinate geometry to five equivalent Y3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on YAsS by Materials Project

YSAs is Matlockite structured and crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Y3+ is bonded in a 9-coordinate geometry to four equivalent As1- and five equivalent S2- atoms. There are a spread of Y–As bond distances ranging from 3.12–3.19 Å. There are a spread of Y–S bond distances ranging from 2.80–2.86 Å. As1- is bonded in a 8-coordinate geometry to four equivalent Y3+ and four equivalent As1- atoms. There are a spread of As–As bond distances ranging from 2.54–2.91 Å. S2- is bonded to five equivalent Y3+ atoms to form a mixture of distorted edge and corner-sharing SY5 trigonal bipyramids.

36 MATERIALS SCIENCE↗
NASA NTRS1974

A low cost ""Air Mass 2'' solar simulator

Tungsten halogen projection lamps have integral ellipsoidal reflector, and hexagonal shaped plastic Fresnel lenses. Reflector is dichroic coated to reduce infrared content of reflected radiation. Array of lamps and lenses produces uniform collimated beam having near AM2 spectrum and intensity that can be used for testing flat plate solar collectors.

Yass, K.↗
NASA NTRS1974

Low-cost, air mass 2 solar simulator

A low cost air mass 2 solar simulator for testing flat-plate solar collectors was developed and operated at Lewis. Total cost was less than $10,800/sq m ($1000/sq ft). It consists of an array of 143 tungsten-halogen 300-watt lamps, each having integral dichroic coated reflectors. A second array of 143 respective hexagonal-shaped plastic Fresnel lenses are located approximately 1 focal length from the lamps. The simulator will produce a uniform collimated beam covering an area of 1.2 by 1.2m(4 by 4 ft). Design features, construction details, and component costs are given, as well as measured results on a 12-lamp prototype.

Yass, K.↗
NASA NTRS1975

Operational performance of a low cost, air mass 2 solar simulator

Modifications and improvements on a low cost air mass 2 solar simulator are discussed. The performance characteristics of total irradiance, uniformity of irradiance, spectral distribution, and beam subtense angle are presented. The simulator consists of an array of tungsten halogen lamps hexagonally spaced in a plane. A corresponding array of plastic Fresnel lenses shapes the output beam such that the simulator irradiates a 1.2 m by 1.2 m area with uniform collimated irradiance. Details are given concerning individual lamp output measurements and placement of the lamps. Originally, only the direct component of solar irradiance was simulated. Since the diffuse component may affect the performance of some collectors, the capability to simulate it is being added. An approach to this diffuse addition is discussed.

Yass, K.↗
NASA NTRS1975

Operational performance of a low cost, air mass 2 solar simulator

The present work describes briefly the design, construction, and operation of a low cost air mass 2 solar simulator, and then presents the performance characteristics of a modified version in terms of total irradiance, uniformity of irradiance, spectral distribution, and beam subtense angle. The simulator consists of an array of 143 tungsten halogen lamps and a corresponding array of 143 Fresnel lenses parallel and in front of the lenses, so that a 1.2 m by 1.2 m area is irradiated with uniform collimated irradiance. The performance of this 143-lamp version is compared with that of the 12-lamp prototype. It was found that the larger design required a lower lamp voltage for an equivalent average total irradiance in the test plane. However, distribution of total irradiance was not as good for the large simulator.

Yass, K.↗