Experimental study of drying of green chili by solar air flat plate collector used obstacles
Keywords:Solar air heaters, solar drying, a new obstacle, thermal efficiency, moisture content, drying rate.
This paper presents the exploitation of the thermal solar energy converter by SAH in drying application. At once, we present the results of an experimental investigation performance for five configurations of air flat plate solar collector at Biskra (latitude 34°48’N and longitude 5°44’E), Algeria. The thermal efficiency between absorber plate and air in flat-plate solar collector has been enhanced by introducing obstacles rows in the dynamic air vein of the collector. A flat plate solar collector, of 1.73 m2 area and 2.5 cm air gap, has been designed and constructed. These obstacles formed with two parts; the first part is perpendicular to fluid flow and the second part is inclined, they are mounted in a staggered pattern, are oriented perpendicular to the fluid flow and are soldered to the back plate. Experiments had been performed for air mass flow rates of 0.018 kg/s and 0.043 kg/s. First case solar air heater without obstacle (case 1) and Four cases of SAH with obstacles (case 2, case3, case 4 and case 5) were tested and compared. The highest efficiency had been obtained in case 5 at 0.043 kg/s. Also, the comparison between the thermal efficiency of the SAH tested in this study with the ones reported in the literature had been presented, and a good agreement had been found. In second parts of this travel, the results of the drying chili were presented. The solar collector Case 5 leads to a very significant improvement in the efficiency/temperature rise couple, and in the reduction in drying time of the product.