EXPERIMENTAL STUDY TO IMPROVE THE PERFORMANCE OF DOUBLE PASS SOLAR AIR HEATER BY USING DIFFERENT NANO-MATERIALS

Abstract

Solar energy is used to heat air, which is then used in greenhouses and to dry crops. Solar air heaters (SAHs) can be made more efficient by employing a new design for the aluminum absorber plate. This solar air heater was compared against a flat absorber plate coated in black paint mixed with titanium oxide (TiO₂), aluminum oxide (Al₂O₃), and copper oxide (CuO) at a 3% concentration. It can help with continuous attempts to improve thermal efficiency and convective heat transfer. This study's analysis is based on experimental data, in which the performance of a double-pass solar air heater design was tested in three examples boosted with nanomaterials at air mass flow rates ranging from 0.05 kg/s to 0.035 kg/s. Based on the findings of the experiments, using nanomaterials containing 3% copper oxide (CuO) is the best instance, with a maximum efficiency of 60.1% at a mass flow rate of 0.05 kg/s. The thermal efficiency of 3% copper oxide ranged from 27.6% to 60.1%, titanium oxide from 30.2% to 55.5%, and aluminum oxide from 30.1% to 55.8%, respectively. When copper oxide was used instead of aluminum oxide, the efficiency increased by 4.6%, whereas titanium oxide increased by 4.3%.