Facet development for a faceted stretched-membrane dish by SAIC

Technical Report · Tue Oct 01 00:00:00 EDT 1991

DOI:https://doi.org/10.2172/5975800· OSTI ID:5975800

The concept for a multi-facet stretched-membrane dish concentrator could reduce the cost and weight of solar thermal dish systems. A stretched-membrane mirror facet for such a multi-facet solar dish concentrator has been developed by Science Applications International Corporation (SAIC). Twelve of the 3.7-m diameter facets will be used to form a 115-m{sup 2} dish concentrator, providing 75 kW{sub th} to operate a 25-kW{sub e} Stirling engine for electric power production. The facet SAIC designed is focused using a vacuum system to elastically deform the thin (0.003-inch thick) stainless steel facet membranes. Elastic focusing was chosen over plastically deforming the membrane to a parabolic shape because it results in a simple manufacturing process. The SAIC facet can be focused from infinity to a minimum focal length-to-diameter ratio of about 2.7. Analytical design studies and experimental tests were performed to evaluate stresses in the ring and membranes during operation, the effects of strain cycling on the reflective surface, and to measure the optical quality of the mirror facets. SAIC produced two prototype mirror facets and they were optically tested at the Solar Energy Research Institute and at Sandia National Laboratories. The first facet showed slope errors ranging from 2.95 to 3.3 mrad over the f/d range of 2.7 to 3.0.

• Research Organization: Sandia National Lab. (SNL-NM), Albuquerque, NM (United States); Science Applications International Corp., San Diego, CA (United States). Energy Projects Div.
• Sponsoring Organization: USDOE; USDOE, Washington, DC (United States)
• DOE Contract Number: AC04-76DP00789
• OSTI ID: 5975800
• Report Number(s): SAND91-7008; ON: DE92004475
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
SOLAR CONCENTRATORS
MATERIALS TESTING
COST ESTIMATION
DESIGN
FABRICATION
HELIOSTATS
MATERIALS
MEMBRANES
MIRRORS
SOLAR THERMAL CONVERSION
STAINLESS STEELS
STIRLING ENGINES
WEIGHT
WELDED JOINTS
ALLOYS
CONVERSION
ENERGY CONVERSION
ENGINES
EQUIPMENT
HEAT ENGINES
HIGH ALLOY STEELS
IRON ALLOYS
IRON BASE ALLOYS
JOINTS
SOLAR ENERGY CONVERSION
SOLAR EQUIPMENT
STEELS
TESTING
CSP
Concentrating Solar Power
141000* - Solar Collectors & Concentrators