Optimized parameters of an air solar collector for drying applications using the experimental design method (DOE)

Abstract

The present study is an optimization of flat plate solar air collector (ASC) in order to improve its thermal performance. A repeated numerical simulation with two software packages TRNSYS and STATGRPHICS has been performed, where TRNSYS software have been used to predict thermal efficiency of different configurations of ASCs and design of experiments method (DOE) have been used to obtain optimum levels of factors affecting the efficiency system. DOE is also used for modeling the outlet temperature of ASC in order to obtain optimal efficiency of the collector. The best conditions founded for optimum outlet temperature and efficiency are as: 2.14 m2 in area, absorber type is stainless steel, glass type is normal glass and air flow is 35 kg / h, where this last factor is the most influential factor on the temperature. Performance of the system was tested and compared with experimental data, and the test results show that the outlet temperature of the new ASC simulated using the optimal conditions, is better with 17 degree compared with ASC before optimization, and the outlet temperature in the winter reaches 41.86 °C when the collector efficiency is 25%, while in the summer it reaches 75°C with efficiency of 16%.