Solar radiation is incident on a 5 m2 solar absorberplate surface at a rate of 800 W/m2. Ninety-three percent ofthe solar radiation is absorbed by the absorber plate, whilethe remaining 7 percent is reflected away. The solar absorberplate has a surface temperature of 40°C with an emissivityof 0.9 that experiences radiation exchange with the surroundingtemperature of -5°C. In addition, convective heat transferoccurs between the absorber plate surface and the ambientair of 20°C with a convection heat transfer coefficient of7 W/m2∙K. Determine the efficiency of the solar absorber,which is defined as the ratio of the usable heat collected bythe absorber to the incident solar radiation on the absorber.

Solar radiation is incident on a 5 m2 solar absorberplate surface at a rate of 800 W/m2. Ninety-three percent ofthe solar radiation is absorbed by the absorber plate, whilethe remaining 7 percent is reflected away. The solar absorberplate has a surface temperature of 40°C with an emissivityof 0.9 that experiences radiation exchange with the surroundingtemperature of -5°C. In addition, convective heat transferoccurs between the absorber plate surface and the ambientair of 20°C with a convection heat transfer coefficient of7 W/m2∙K. Determine the efficiency of the solar absorber,which is defined as the ratio of the usable heat collected bythe absorber to the incident solar radiation on the absorber.

University Physics Volume 2

18th Edition

ISBN:9781938168161

Author:OpenStax

Publisher:OpenStax

Chapter1: Temperature And Heat

Section: Chapter Questions

Problem 100P: One easy way to reduce heating (and cooling) costs is to add extra insulation in the attic of a...

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