Cylindrical glass tube honeycomb solar collector studies

Technical Report · Tue Aug 01 04:00:00 EDT 1978

OSTI ID:6690026

Lewandowski, A A

The performance of cylindrical glass tube honeycomb solar collectors was examined both experimentally and analytically. Two 0.61 m x 0.61 m experimental solar collectors were designed, fabricated and tested. A single, scaled-up 0.43 m x 1.27 m collector was designed and fabricated to incorporate a cylindrical glass tube honeycomb and tested. Quasisteady-state tests showed that the cylindrical glass tube honeycomb collector was a superior performer at inlet-minus-ambient temperature differences greater than 35/sup 0/C compared to two commercial collectors: a double-glazed, non-selective black unit and a single-glazed, selective black unit. A non-linear steady-state thermal network was used to predict collector performance. Excellent agreement between experimental and predicted efficiency was obtained. Root-mean-square (RMS) differences between experimental and predicted efficiency for the two collectors tested at UCLA were 0.036 and 0.015, respectively; the RMS difference for the collector tested at Lockheed was 0.029. Design guidelines were updated for cylindrical glass tube honeycombs to include the effect of temperature level on cell dimensions required to suppress convection. Inside diameters of 1.3 - 1.6 cm and cell lengths of 6-9 cm were recommended for thin walled glass tubes used as honeycomb cells in flat-plate solar collectors for applications where the collector operates at 80/sup 0/C or higher. (WHK)

• Research Organization: California Univ., Los Angeles (USA). School of Engineering and Applied Science
• DOE Contract Number: FG03-76CS31084
• OSTI ID: 6690026
• Report Number(s): UCLA-ENG-7847
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
141000* -- Solar Collectors & Concentrators
ANALYTICAL SOLUTION
CONFIGURATION
CYLINDRICAL CONFIGURATION
DESIGN
DIFFUSE SOLAR RADIATION
DIMENSIONS
DIRECT SOLAR RADIATION
EFFICIENCY
ENERGY LOSSES
EQUIPMENT
ERRORS
FLAT PLATE COLLECTORS
GLASS
HEAT LOSSES
HONEYCOMB STRUCTURES
LIGHT TRANSMISSION
LOSSES
MECHANICAL STRUCTURES
PERFORMANCE
PERFORMANCE TESTING
RADIATIONS
SOLAR COLLECTORS
SOLAR EQUIPMENT
SOLAR FLUX
SOLAR RADIATION
STELLAR RADIATION
TESTING
THERMAL ANALYSIS
TUBES