View-limiting shrouds for insolation radiometers

Technical Report · Wed May 15 00:00:00 EDT 1985

DOI:https://doi.org/10.2172/5392504· OSTI ID:5392504

Dennison, E. W.; Trentelman, G. F.

Insolation radiometers (normal incidence pyrheliometers) are used to measure the solar radiation incident on solar concentrators for calibrating thermal power generation measurements. The measured insolation value is dependent on the atmospheric transparency, solar elevation angle, circumsolar radiation, and radiometer field of view. The radiant energy entering the thermal receiver is dependent on the same factors. The insolation value and the receiver input will be proportional if the concentrator and the radiometer have similar fields of view. This report describes one practical method for matching the field of view of a radiometer to that of a solar concentrator. The concentrator field of view can be calculated by optical ray tracing methods, and the field of view of a radiometer with a simple shroud can be calculated by using geometric equations. The parameters for the shroud can be adjusted to provide an acceptable match between the respective fields of view. Concentrator fields of view have been calculated for a family of paraboloidal concentrators and receiver apertures. The corresponding shroud parameters have also been determined. The effectiveness of this technique has been tested by comparing radiometer and concentrator measurements under a variety of sky conditions. Appropriate radiometer shrouds should be used to obtain accurate insolution measurements for determining solar concentrator and power conversion system efficiencies and for site surveys.

• Research Organization: California Institute of Technology (CalTech), Pasadena, CA (United States). Jet Propulsion Lab. (JPL)
• DOE Contract Number: AM04-80AL13137
• OSTI ID: 5392504
• Report Number(s): DOE/JPL-1060-88; JPL-PUB-85-54; ON: DE85017590
• Country of Publication: United States
• Language: English

Related Subjects

14 SOLAR ENERGY
RADIOMETERS
PERFORMANCE TESTING
ACCURACY
APERTURES
CALIBRATION
CALORIMETERS
GEOMETRY
INSOLATION
PARABOLIC DISH COLLECTORS
PYRHELIOMETERS
CONCENTRATING COLLECTORS
EQUIPMENT
MATHEMATICS
MEASURING INSTRUMENTS
OPENINGS
PARABOLIC COLLECTORS
RADIATION DETECTORS
SOLAR COLLECTORS
SOLAR EQUIPMENT
TELESCOPES
TESTING
140100* - Solar Energy- Resources & Availability