Inflatable concentrators for solar propulsion and dynamic space power

Journal Article · Thu Nov 01 00:00:00 EST 1990 · Journal of Solar Energy Engineering; (USA)

DOI:https://doi.org/10.1115/1.2929928· OSTI ID:5668628

Grossman, G; Williams, G ^[1]

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1. L'Garde, Inc., Tustin, CA (US)

This paper describes the development of an inflatable concentrator for solar propulsion, providing the source of heat to a hydrogen engine aboard the Solar Rocket. The latter is a device designed to carry payloads from a low earth orbit (LEO) to a geosynchronous orbit (GEO) at significant mass savings in comparison to chemical propulsion; it involves two light-weight parabolic reflectors in an off-axis configuration focusing solar radiation into the absorbers of the engine, which causes the emission of a hot hydrogen jet. Each of the reflectors has an elliptical rim with a 40 m major axis, providing heat to the propellant sufficient to produce about 40 lbs. of thrust. The same concentrator concept is contemplated for space power application to focus solar radiation on a conversion device, e.g., a photovoltaic array or the high temperature end of a dynamic engine. Under the present project, a one-fourth scale, 9X7 m off-axis inflatable concentrator has been under development as a pilot for the full-scale flight unit. The reflector component consists of a reflective membrane made of specially designed gores and a geometrically identical transparent canopy. The two form together an inflatable lenslike structure which, upon inflation, assumes the accurate paraboloidal shape. This inflatable structure is supported along its rim by a strong, bending-resistant torus. The paper describes the development of this system including the analysis leading to determination of the gore shapes, the reflector membrane design and testing, the analysis of the supporting torus, and a discussion of the effects of the space environment.

• OSTI ID: 5668628
• Journal Information: Journal of Solar Energy Engineering; (USA), Vol. 112:4; ISSN 0199-6231
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
PROPULSION SYSTEMS
INFLATABLE COLLECTORS
ROCKET ENGINES
SOLAR POWER PLANTS
DESIGN
HYDROGEN
LENSES
MEMBRANES
PARABOLIC DISH REFLECTORS
PERFORMANCE TESTING
SOLAR RADIATION
ELEMENTS
ENGINES
EQUIPMENT
NONMETALS
PARABOLIC REFLECTORS
POWER PLANTS
RADIATIONS
SOLAR COLLECTORS
SOLAR CONCENTRATORS
SOLAR EQUIPMENT
SOLAR REFLECTORS
STELLAR RADIATION
TESTING
141000* - Solar Collectors & Concentrators