Development of a Wind-Ventilated Box-Type Absorber Solar Air Collector
Abstract
This paper presents the design, construction and performance evaluation of a wind-ventilated box-type absorber solar air collector. A box absorber was used to transfer heat to the air stream via a larger surface area than ordinary flat-plate absorber and a rotary wind ventilator was incorporated to exploit the benefits of using forced convection solar dryers in the remote areas where electricity and other power source are non-existent. During the tests, maximum temperatures of 62.5 and 58.50C were obtained inside the collector and drying chamber, respectively, while the maximum ambient temperature obtained was 33.00C. The system drying efficiency increases as the air velocity through the system increases. The average air velocity obtained through the solar dryer was 1.76 ms– 1 and the average drying efficiency of the system was 40.9%. The dryer performance was optimum from 12.00 hour to 15.00 hour. The maximum collector efficiency and average collector daily efficiency obtained were 55.2 and 41.0%, respectively.
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