Experimental investigation and two-factor factorial analysis of a solar air heater with scrap wire meshes and cans as energy storage components

Abstract

This study investigates the performance of a solar air heater with scrap materials. No absorber sheet was included in the system, just scrap aluminum cans and wire meshes were used as its absorber to store and transfer solar energy to air. The arrangement of components inside the collector was varied and each configuration was tested with different air mass flow rates. Three different configurations included: vertically arranged cans, vertically arranged cans with meshes and horizontally arranged cans and their mean thermal efficiencies were found as 40.7 %, 45.8 % and 63.4 % at the highest airflow rate (0.043 kg/s m2), respectively. The highest performance (82.2 %) was obtained from the collector with horizontally arranged cans at the same mass flow rate. It was also found that the collector efficiency increases as rolled mesh layers added alongside cans. The pressure drop was considerably low (2 to 14 Pa) in all the setups. The two-factor factorial design method was used to evaluate the experimental data obtained in this study. The analysis showed that both factors (Collector arrangement and airflow rate) had significant effects on the thermal performance of the system.