Improvement in the performance of the evacuated tube solar collector by an electronic curtain made of acrylic mirror and adding aluminium oxide nanoparticles

Solar collectors are thermal equipment that receives solar energy by absorbing sunlight and converting it into thermal energy. The working fluid is the most important part of the system, as nanomaterials were used with water instead of pure water, as this method is one of the best ways to increase the performance of the solar collector. In this study, the performance of the evacuated tube solar collector was improved by designing an electronic curtain made of acrylic mirror, in addition to adding nanoparticles of Al2O3 to a liquid work (water). A volume fraction of nanoparticles of 1%, 3%, and 5% was used at flow rates of (3, 9, 15 )L/min. The performance of a vacuum tube solar collector was compared using Al2O3 and water within the stated flow rates. Through the results obtained, it was found that the efficiency of the solar collector increases with the increase in the concentrations of the nanomaterial and the presence of acrylic mirrors on both sides of the evacuated tubes as a reflective surface.