Fixed tilt solar collector employing reversible vee-trough reflectors and evacuated tube receivers for solar heating and cooling systems. Final report, Phase II data acquisition

Technical Report · Sun Oct 15 04:00:00 EDT 1978

DOI:https://doi.org/10.2172/6082953· OSTI ID:6082953

Selcuk, M K

The objective of the Vee-Trough/Evacuated Tube Collector (VTETC) Project, undertaken for the DOE Solar Heating and Cooling Branch, was to show how vee-trough concentrators could improve the heat collection capability and reduce the cost of collectors consisting of evacuated tube receivers. The work was carried out in two phases. During the first phase, the VTETC was analyzed rigorously and various mathematical models were developed to calculate the optical performance of the vee-trough concentrators and the thermal performance of the evacuated tube receivers. A test bed was constructed to verify the mathematical analyses and compare reflectors made of back-silvered glass mirror, Alzak, Aluminized Teflon, and Kinglux (an electro polished aluminum reflector). Testing was conducted and data was obtained for the months of April to August 1977. The results of the mathematical analyses, as well as the results from 1977, were reported in DOE/JPL/1024-1, published in January 1978. In the second phase, additional tests were run at temperatures ranging from 80 to 190/sup 0/C (176 to 374/sup 0/F) during the months of April, May, June, and July 1978. The results obtained compared well with theoretical predictions. For the glass mirror reflectors, peak efficiencies, based on aperture area and operating temperatures of 125/sup 0/C (257/sup 0/F), were over 40%. Efficiencies of about 40% were observed at temperatures of 150/sup 0/C (302/sup 0/F) and 30% at 175/sup 0/C (347/sup 0/F). Test data covering a complete day are presented for selected dates throughout the test season. Predicted daily useful heats collected and efficiency values are presented for a full year. These theoretical values are then compared with actual data points for the same temperature range.

• Research Organization: Jet Propulsion Lab., Pasadena, CA (USA)
• DOE Contract Number: EX-76-A-29-1024
• OSTI ID: 6082953
• Report Number(s): DOE/JPL-1024-78/1; JPL-PUB-78-106
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
140901 -- Solar Thermal Utilization-- Space Heating & Cooling
141000* -- Solar Collectors & Concentrators
COMPUTER CALCULATIONS
CONCENTRATING COLLECTORS
DATA
DESIGN
EFFICIENCY
ENERGY LOSSES
EVACUATED COLLECTORS
EVACUATED TUBE COLLECTORS
HEAT LOSSES
HEATING SYSTEMS
INFORMATION
LOSSES
MATERIALS
MATHEMATICAL MODELS
OPTICS
PERFORMANCE
PERFORMANCE TESTING
SOLAR COLLECTORS
SOLAR CONCENTRATORS
SOLAR COOLING SYSTEMS
SOLAR HEATING SYSTEMS
SOLAR REFLECTORS
TEST FACILITIES
TESTING
V TROUGH COLLECTORS