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Standard analyses of solar collector thermal performance are based upon an energy balance in which the environments adjoining the front and rear of the collector are assumed to be at the same temperature. This assumption is inappropriate for some collector designs, particularly building-integrated collectors. An approach for analyzing such situations is presented based upon a new conceptual temperature termed the 'equivalent ambient temperature.' The concept is explained, the new temperature is defined, and the approach is applied to a typical collector geometry. The approach retains the convenience of the standard analysis while accounting for the unequal front/rear ambient temperatures and permits collector characterization in terms of the conventional parameters: plate efficiency factor, F'; heat removal factor, [F.sub.R] ; overall heat loss coefficient, [U.sub.L], and effective transmittance--absorptance product, [([TAU][alpha]).sub.e]. [DOI: 10.1115/1.1488165]

An approach based on a new conceptual temperature termed the 'equivalent ambient temperature' has been introduced for analyzing solar collector thermal performances when the environments to the front and rear of a collector are at different temperatures. Using a specially-designed solar simulator, experimental work is presented which validates the new approach as applied to a wall-integrated covered profiled metal solar air collector. Using both the new and traditional approaches, collector thermal performances are predicted to reveal the practical conditions for which use of the new approach is warranted. The latter findings will be of importance to designers. Performance characteristics for this collector geometry are also presented for use by designers. [DOI: 10.1115/1.1488166]

Presents a validation and design for the approach used in analyzing solar collectors subjected to unequal front and rear ambient temperatures. Study of the equivalent ambient temperature concept; Collector air flow and measurement; Solar simulator design; Surface wind simulation; Solar irradiance and transmittance.

Describes an approach for analyzing solar collectors subjected to unequal front and rear ambient temperatures. Study of the equivalent ambient temperature concept; Collector thermal modeling; Evaluation of solar collector thermal performances.