JOURNAL OF THE FACULTY OF ENGINEERING AND ARCHITECTURE OF GAZI UNIVERSITY, vol.28, no.4, pp.733-741, 2013 (SCI-Expanded)
A solar energy and heat pump dryer was designed, manufactured and investigated experimentally by drying kiwi. Kiwis sliced into 5 mm thickness were dried from initial moisture content 6 g water/g dry matter to final moisture content at 35 degrees C -0,53 g water/g dry matter, at 40 degrees C -0,25 g water/g dry matter at 45 degrees C -0,14 g water/g dry matter and at 50 degrees C -0,15 g water/g dry matter. Kiwis were dried at the temperature of drying air 50 degrees C, 45 degrees C, 40 degrees C and 35 degrees C, variable air velocity (0,1-1,0 m/s) and 8,5 hours, 7,5 hours, 7,5 hours and 6,5 hours, respectively. Coefficient of performance of heat pump (COPhp,h) and whole system coefficient of performance of heat pump (COPts) were calculated as average 2,90 and 2,27 for all experiments, respectively. Average efficiency of wavy finned air solar collector was calculated as 56,7% for all experiments. The appropriate drying air temperature has been determined as 50 degrees C for kiwi drying with this experimental study.