Fe3O4 나노유체 활용 체적형 직접흡수식 태양열 집열기 효율에 대한 실험적 연구

Abstract

This study experimentally investigated the optical absorption characteristics of Fe3O4 nanofluid and the performance improvement of volumetric absorption solar collectors when using the Fe3O4 nanofluid to improve the performance of the volume absorption solar collector. As a result of the experiment, it was confirmed that the Fe3O4 nanofluid has excellent light absorption in the ultraviolet and visible light bands. It addition the solar weighted absorption coefficient of 0.1wt% Fe3O4 nanofluid was 0.927, which is higher than that of 0.595, which is the solar weighted absorption coefficient of water. When the Fe3O4 nanofluid was used as the working fluid of the volumetric absorption solar collector, the performance of the solar collector was improved. As the concentration of the Fe3O4 nanofluid increased from 0wt% to 0.1wt%, the temperature difference at the inlet and outlet of the volumetric absorption solar collector increased, the useful heat increased, and the heat collection efficiency increased. In addition, the increase in mass flow contributed to the improvement of the efficiency of the volumetric absorption solar collector by utilizing the Fe3O4 nanofluid. Increasing the mass flow rate decreased the average temperature of the volumetric absorption solar collector, reducing heat loss, and increasing the efficiency of the volumetric absorption solar collector.