MATHEMATICAL MODELING AND EXPERIMENTAL STUDY OF PISTACHIO DRYING BEHAVIOR IN A MIXED MODE PV OPERATED FORCED CONVECTION SOLAR DRYER

In Shahid Bahonar University of Kerman-southeast of Iran- a mixed-mode solar dryer specimen has been designed, manufactured and tested in late summer and early fall to investigate its performance, efficiency and drying process of various agricultural products. The device has been tested with pistachio which must has top-level quality and toxics especially aflatoxin less than 1 ppb. This strict conditions demands consideration about how one grow, harvest and post-harvest this product. Alternative sources for suction fans have been used. During the experiments essential parameters for calculating its performance and modeling the process like ambient temperature, temperature inside the collector and drying chamber, velocity and moisture content of heated air, solar radiation and weight of product were measured. The maximum temperature inside chamber at the end of harvest season is about 60ºC, which was at least 20ºC above ambient temperature from 8 am to 4pm. Also a mathematical modeling which based on equations of heat and mass conservation was performed. Numerical results such as product temperature profile, remained moisture content of pistachio in different racks and drying rate due to time were plotted and compared with experimental counterparts. It was found that proposed model have a sufficient accuracy with experimental results for forced convection dryers.

کلیدواژه ها:

solar dryer ، forced convection ، mathematical modeling ، mass and heat conservation ، pistachio