Effect of pressure-induced stress on the design of shaped-glass evacuated solar collectors

Journal Article · Tue Jun 01 04:00:00 EDT 1993 · Solar Energy (Journal of Solar Energy Science and Engineering); (United States)

DOI:https://doi.org/10.1016/0038-092X(93)90115-5· OSTI ID:6310190

Garrison, J D ^[1]

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1. San Diego State Univ., CA (United States)

Shaped-glass evacuated solar collectors have the lower portion of the tubular glass vacuum envelope shaped and inside surface mirrored to concentrate sunlight onto an absorber tube in the vacuum. Upon evacuation, stresses are set up in the glass. The maximum surface tensile stress possible in glass, while keeping the probability of fracture small, is of the order of 7 MPa. This low maximum tensile stress places severe limitations on the amount the lower portion of the cross section of a cylindrical glass evacuated solar collector can deviate from circular to provide the concentration. Equations are developed for determining stress in the glass. Results of stress calculations leading to parameters for collector design are presented.

• OSTI ID: 6310190
• Journal Information: Solar Energy (Journal of Solar Energy Science and Engineering); (United States), Journal Name: Solar Energy (Journal of Solar Energy Science and Engineering); (United States) Vol. 50:6; ISSN 0038-092X; ISSN SRENA4
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
141000* -- Solar Collectors & Concentrators
ATMOSPHERIC PRESSURE
DESIGN
EQUATIONS
EQUIPMENT
EVACUATED COLLECTORS
EVACUATED TUBE COLLECTORS
FRACTURING
GLASS
MECHANICAL PROPERTIES
SOLAR COLLECTORS
SOLAR EQUIPMENT
STRESSES
SURFACE PROPERTIES
SURFACE TENSION
TENSILE PROPERTIES